    % Document-style collection for journals published by Elsevier Science.
    % To be used with LaTeX version 2.09 of 14 January 1992 (or later)
    %
    % Version: 2.23
    % Date:    4 July 1995
    %
    % Copyright (C) 1994 by Elsevier Science. All rights reserved.
    %
    % IMPORTANT NOTICE:
    %
    % You are not allowed to change this file. You may however copy this file
    % to a file with a different name and then change the copy.
    %
    % You are NOT ALLOWED to distribute this file alone. You are NOT ALLOWED
    % to take money for the distribution or use of this file (or a changed
    % version) except for a nominal charge for copying etc.
    %
    % You are allowed to distribute this file under the condition that it is
    % distributed together with all files mentioned in readme.els.
    %
    % If you receive only some of these files from someone, complain!
    %
    %
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    \def\esp@filedate{4 July 1995}
    \def\@shortjnl{\@nil}
    \def\@@shortjnl{\@nil}
    \def\@journal{Elsevier Science}
    \def\@issn{0}
    \def\@jid{ELSART} \def\@shortjid{elsart}
    \typeout{Elsevier Science preprint document style
    \esp@fileversion \space\space <\esp@filedate>}
    \def\partname{Part}
    \def\contentsname{Contents}
    \def\listfigurename{List of Figures}
    \def\listtablename{List of Tables}
    \def\refname{References}
    \def\indexname{Index}
    \def\figurename{Fig.}
    \def\tablename{Table}
    \def\abstractname{Abstract}
    \def\@ptsize{2}
    \def\ds@twoside{\@twosidetrue
                    \@mparswitchtrue}
    \def\ds@oneside{\@twosidefalse
                    \@mparswitchfalse}
    \@twocolumnfalse
    \newif\if@TwoColumn
    \def\ds@onecolumn{\@twocolumnfalse
                      \@TwoColumnfalse}
    \def\ds@twocolumn{\@twocolumnfalse
                      \@TwoColumntrue}
    \@TwoColumnfalse
    \@twosidefalse
    \@namedef{ds@10pt}{}
    \@namedef{ds@11pt}{}
    \def\ds@fleqn{}
    \def\@pagenumprefix{}
    \newif\if@draft \@draftfalse
    \def\query{}
    \def\ds@draft{%
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    \def\query{\marginpar{???}}%
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    \newif\if@secthm
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    \newif\if@secfloat
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    \def\ds@secfloat{\@secfloattrue}
    \def\ds@secnum{\@seceqntrue \@secfloattrue \@secthmtrue}%
    \newif\if@nameyear
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    \def\ds@nameyear{\@nameyeartrue}
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    \def\labelitemi{--}
    \def\labelitemii{$\cdot$}
    \def\labelenumi{(\theenumi)}        \def\theenumi{\roman{enumi}}
    \def\labelenumii{(\theenumii)}      \def\theenumii{\alph{enumii}}
    	\def\p@enumii{\theenumi}
    \def\enumerate{%
      \ifnum \@enumdepth >\@maxlistdepth
        \@toodeep
      \else
        \advance\@enumdepth \@ne
        \edef\@enumctr{enum\romannumeral\the\@enumdepth}%
        \list{\csname label\@enumctr\endcsname}%
           {\usecounter{\@enumctr}
           \let\makelabel=\right@label}
      \fi}
    \def\itemize{%
      \ifnum \@itemdepth >\@maxlistdepth
        \@toodeep
      \else
        \advance\@itemdepth \@ne
        \edef\@itemitem{labelitem\romannumeral\the\@itemdepth}%
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        \setleftmargin{ii}{$\cdot$}%
        \list{\csname\@itemitem\endcsname}%
           {\let\makelabel\right@label}
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    \def\verse{\let\\=\@centercr
      \list{}{\itemsep\z@
      \itemindent \z@
      \listparindent\z@
      \rightmargin 1em
      \leftmargin \rightmargin}\item[]}
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    \let\endquotation=\endlist
    \def\quote{\list{}{\itemindent\z@
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    \let\endquote=\endlist
    \def\descriptionlabel#1{\hspace\labelsep \bf #1}
    \def\description{\list{}{\labelwidth\z@
      \leftmargin 1em \itemindent-\leftmargin
      \let\makelabel\descriptionlabel}}
    \let\enddescription\endlist
    \def\operatorname#1{\mathop{\mathrm{#1}}\nolimits}
    \def\lefteqn#1{\hbox to\z@{$\displaystyle {#1}$\hss}}
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    \jot=2pt
    \newskip\eqnlineskip
    \eqnbaselineskip=14pt  \eqnlineskip=2pt
    \newdimen\mathindent
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      \mathindent 2em
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      \noindent
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      \belowdisplayshortskip\abovedisplayskip
      \abovedisplayshortskip\abovedisplayskip
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        \pre@colii$\displaystyle{##}$\post@colii
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        \pre@coliii $\displaystyle\tabskip\z@{##}$\post@coliii
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    \def\endeqnarray{\@@eqncr\egroup
     \global\advance\c@equation\m@ne$$\global\@ignoretrue }
    \def\pre@coli{\hskip\@centering}              \def\post@coli{}
    \def\pre@colii{\hskip 2\eqnarraycolsep \hfil} \def\post@colii{\hfil}
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    \newcounter{subparagraph}[paragraph]
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    \newcounter{figure}
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     \def\theequation{\arabic{equation}}
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    \if@secfloat
     \@addtoreset{table}{section}
     \def\thetable{\arabic{section}.\arabic{table}}
     \@addtoreset{figure}{section}
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     \def\thefigure{\arabic{figure}}
     \def\thetable{\arabic{table}}
    \fi
    \def\thesection      {\arabic{section}}
    \def\thesubsection   {\thesection.\arabic{subsection}}
    \def\thesubsubsection{\thesubsection.\arabic{subsubsection}}
    \def\theparagraph    {\thesubsubsection.\arabic{paragraph}}
    \def\thesubparagraph {\theparagraph.\arabic{subparagraph}}
    \def\qed{\relax\ifmmode\hskip2em \Box\else\unskip\nobreak\hskip1em $\Box$\fi}
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      {\par\addvspace{\@bls plus 0.5\@bls minus 0.1\@bls}}
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     \newtheorem{thm}{Theorem}[section]
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     \newtheorem{thm}{Theorem}
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    \newtheorem{cor}[thm]{Corollary}
    \newtheorem{lem}[thm]{Lemma}
    \newtheorem{claim}[thm]{Claim}
    \newtheorem{axiom}[thm]{Axiom}
    \newtheorem{conj}[thm]{Conjecture}
    \newtheorem{fact}[thm]{Fact}
    \newtheorem{hypo}[thm]{Hypothesis}
    \newtheorem{assum}[thm]{Assumption}
    \newtheorem{prop}[thm]{Proposition}
    \newtheorem{crit}[thm]{Criterion}
    \newtheorem{defn}[thm]{Definition}
    \newtheorem{exmp}[thm]{Example}
    \newtheorem{rem}[thm]{Remark}
    \newtheorem{prob}[thm]{Problem}
    \newtheorem{prin}[thm]{Principle}
    \newtheorem{alg}{Algorithm}
    \long\def\@makealgocaption#1#2{\vskip 2ex \small
      \hbox to \hsize{\parbox[t]{\hsize}{{\bf #1.} #2}}}
    \newcounter{algorithm}
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    \def\fps@algorithm{tbp}
    \def\ftype@algorithm{4}
    \def\ext@algorithm{lof}
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    \def\algorithm{\let\@makecaption\@makealgocaption\@float{algorithm}}
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    \newtheorem{note}{Note}
    \newtheorem{summ}{Summary}
    \newtheorem{case}{Case}
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    \def\@tocrmarg{2.55em plus 5em}
    \def\@dotsep{-2.5}
    \setcounter{tocdepth}{2}
    \def\tableofcontents{%
      \section*{\contentsname}%
      \@starttoc{toc}}
    \def\l@section{\@dottedtocline{1}{0.0em}{1.40em}}
    \def\l@subsection{\@dottedtocline{2}{1.40em}{2.24em}}
    \def\l@subsubsection{\@dottedtocline{3}{2.24em}{3.09em}}
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      \@startsection{section}{1}{\z@}{20pt plus 8pt minus 4pt}
      {\@bls}{\normalsize\bf}*{\refname}%
      \addcontentsline{toc}{section}{\refname}%
      \@thebibliography}
    \let\endthebibliography=\endlist
    \def\@thebibliography#1{
      \small
      \list{\@biblabel{\arabic{enumiv}}}{\settowidth\labelwidth{\@biblabel{#1}}
      \if@nameyear
        \labelwidth\z@ \labelsep\z@ \leftmargin\parindent
        \itemindent-\parindent
      \else
        \labelsep 3pt \itemindent\z@
        \leftmargin\labelwidth \advance\leftmargin\labelsep
    \fi
        \itemsep 0.3\@bls plus 0.1\@bls minus 0.1\@bls
        \usecounter{enumiv}\let\p@enumiv\@empty
        \def\theenumiv{\arabic{enumiv}}}%
        \def\newblock{\hskip 0.11em plus 0.33em minus -0.07em}
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    \if@nameyear
      \def\@biblabel#1{}
    \else
      \def\@biblabel#1{\hskip \z@ plus 1filll[#1]}
    \fi
    \newcount\@tempcntc
    \def\@citex[#1]#2{\if@filesw\immediate\write\@auxout{\string\citation{#2}}\fi
     \@tempcnta\z@\@tempcntb\m@ne\def\@citea{}\@cite{\@for\@citeb:=#2\do
      {\@ifundefined
       {b@\@citeb}{\@citeo\@tempcntb\m@ne\@citea\def\@citea{,}{\bf ?}\@warning
       {Citation `\@citeb' on page \thepage \space undefined}}%
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       \ifnum\@tempcntc=\z@ \@citeo\@tempcntb\m@ne
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       \else
        \advance\@tempcntb\@ne
        \ifnum\@tempcntb=\@tempcntc
        \else\advance\@tempcntb\m@ne\@citeo
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    \def\@citeo{\ifnum\@tempcnta>\@tempcntb\else\@citea\def\@citea{,}%
     \ifnum\@tempcnta=\@tempcntb\the\@tempcnta\else
      {\advance\@tempcnta\@ne\ifnum\@tempcnta=\@tempcntb \else \def\@citea{--}\fi
       \advance\@tempcnta\m@ne\the\@tempcnta\@citea\the\@tempcntb}\fi\fi}
    \@namedef{cv*}{\section*{Curriculum Vitae}\cv}
    \def\cv{\hangindent=7pc \hangafter=-12 \parskip\bigskipamount \small}
    \def\footnote{\@ifnextchar[{\@xfootnote}{\refstepcounter
       {\@mpfn}\xdef\@thefnmark{\thempfn}\@footnotemark\@footnotetext}}
    \def\footnotemark{\@ifnextchar[{\@xfootnotemark
        }{\refstepcounter{footnote}\xdef\@thefnmark{\thefootnote}\@footnotemark}}
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      \@ifnextchar[{\@xmpfootnotemark}{\stepcounter{mpfootnote}%
      \begingroup
        \let\protect\noexpand
        \xdef\@thefnmark{\thempfootnote}%
      \endgroup
      \@footnotemark}}
    \def\@xmpfootnotemark[#1]{%
      \begingroup
        \c@mpfootnote #1\relax
        \let\protect\noexpand
        \xdef\@thefnmark{\thempfootnote}%
      \endgroup
      \@footnotemark}
    \def\@mpmakefnmark{\,\hbox{$^{\mathrm{\@thefnmark}}$}}
    \long\def\@mpmakefntext#1{\noindent
                         \hbox{$^{\mathrm{\@thefnmark}}$} #1}
    \def\@iminipage[#1]#2{\leavevmode
      \@pboxswfalse
      \if #1b\vbox
      \else \if #1t\vtop
      \else \ifmmode \vcenter
      \else \@pboxswtrue $\vcenter
      \fi \fi \fi
      \bgroup \hsize #2\textwidth\hsize \columnwidth\hsize
      \@parboxrestore
      \def\@mpfn{mpfootnote}\def\thempfn{\thempfootnote}\c@mpfootnote\z@
      \let\@footnotetext\@mpfootnotetext
      \let\@makefntext\@mpmakefntext
      \let\@makefnmark\@mpmakefnmark
      \let\@listdepth\@mplistdepth \@mplistdepth\z@
      \@minipagerestore\global\@minipagetrue
      \everypar{\global\@minipagefalse\everypar{}}}
    \def\fn@presym{}
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    \def\textfraction{0.05}
    \def\floatpagefraction{0.9}
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    \def\bottomfraction{0.99}
    \setcounter{totalnumber}{10}
    \def\dbltopfraction{0.99}
    \def\dblfloatpagefraction{0.8}
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    \newbox\@tempboxb
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      \hbox to \hsize{\parbox[t]{\hsize}{#1 \\ #2}}}
    \long\def\@makefigurecaption#1#2{\small
      \vskip 8pt
      \setbox\@tempboxa\hbox{#1. #2}
      \ifdim \wd\@tempboxa >\hsize
        \unhbox\@tempboxa\par
      \else
        \hbox to\hsize{\hfil\box\@tempboxa\hfil}%
      \fi}
    \def\conttablecaption{\par \begingroup \@parboxrestore \normalsize
      \@makecaption{\fnum@table\,---\,continued}{}\par
      \vskip-1pc \endgroup}
    \def\contfigurecaption{\vskip-1pc \par \begingroup \@parboxrestore \normalsize
      \@makecaption{\fnum@figure\,---\,continued}{}\par
      \endgroup}
    \def\fps@figure{tbp}
    \def\ftype@figure{1}
    \def\ext@figure{lof}
    \def\fnum@figure{\figurename~\thefigure}
    \def\figure{\let\@makecaption\@makefigurecaption
      \let\contcaption\contfigurecaption \@float{figure}}
    \let\endfigure\end@float
    \@namedef{figure*}{\let\@makecaption\@makefigurecaption
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    \def\fps@table{tbp}
    \def\ftype@table{2}
    \def\ext@table{lot}
    \def\fnum@table{\tablename~\thetable}
    \def\table{\let\@makecaption\@maketablecaption \small
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      \let\contcaption\conttablecaption \@float{table}}
    \let\endtable\end@float
    \@namedef{table*}{\let\@makecaption\@maketablecaption \small
      \let\footnoterule\relax
      \let\contcaption\conttablecaption \@dblfloat{table}}
    \@namedef{endtable*}{\end@dblfloat}
    \newtoks\t@glob@notes
    \newtoks\t@loc@notes
    \newcount\note@cnt
    \newcounter{author}
    \newcount\n@author
    \def\n@author@{}
    \newcounter{collab}
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    \newcounter{address}
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    \newcount\sv@hyphenpenalty
    \newcount\prev@elem \prev@elem=0
    \newcount\cur@elem  \cur@elem=0
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    \chardef\e@subtitle=1
    \chardef\e@author=2
    \chardef\e@collab=3
    \chardef\e@address=4
    \newif\if@newelem
    \newif\if@firstauthor
    \newif\if@preface
    \newif\if@hasabstract
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    \newbox\t@keyword
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    \def\add@xtok#1#2{\begingroup
      \no@harm
      \xdef\@act{\global\noexpand#1{\the#1#2}}\@act
    \endgroup}
    \def\beg@elem{\global\t@loc@notes={}\global\note@cnt\z@}
    \def\@xnamedef#1{\expandafter\xdef\csname #1\endcsname}
    \def\no@harm{%
      \let\\=\relax  \let\rm\relax
      \let\ss=\relax \let\ae=\relax \let\oe=\relax
      \let\AE=\relax \let\OE=\relax
      \let\o=\relax  \let\O=\relax
      \let\i=\relax  \let\j=\relax
      \let\aa=\relax \let\AA=\relax
      \let\l=\relax  \let\L=\relax
      \let\d=\relax  \let\b=\relax \let\c=\relax
      \let\bar=\relax
      \def\protect{\noexpand\protect\noexpand}}
    \def\proc@elem#1#2{\begingroup
        \no@harm
        \let\thanksref\@gobble
        \@xnamedef{@#1}{#2}%
      \endgroup
      \prev@elem=\cur@elem
      \cur@elem=\csname e@#1\endcsname
      \expandafter\elem@nothanksref#2\thanksref\relax}
    \def\elem@nothanksref#1\thanksref{\futurelet\@peektok\elem@thanksref}
    \def\elem@thanksref{\ifx\@peektok\relax
      \else \expandafter\elem@morethanksref \fi}
    \def\elem@morethanksref#1{\add@thanksref{#1}\elem@nothanksref}
    \def\add@thanksref#1{\global\advance\note@cnt\@ne
      \ifnum\note@cnt>\@ne \add@xtok\t@loc@notes{\note@sep}\fi
      \add@tok\t@loc@notes{\ref{#1}}}
    \def\note@sep{,}
    \def\thanks{\@ifnextchar[{\@tempswatrue
      \thanks@optarg}{\@tempswafalse\thanks@optarg[]}}
    \def\thanks@optarg[#1]#2{\refstepcounter{footnote}\if@tempswa
      \label{#1}\else\relax\fi
      \add@tok\t@glob@notes{\footnotetext}%
      \add@xtok\t@glob@notes{[\the\c@footnote]}%
      \add@tok\t@glob@notes{{#2}}}
    \def\frontmatter{%
      \let\@corresp@note\relax
      \global\t@glob@notes={}\global\c@author\z@
      \global\c@collab\z@ \global\c@address\z@
      \sv@mathsurround\mathsurround \m@th
      \global\n@author=0\n@author@\relax
      \global\n@collab=0\n@collab@\relax
      \global\advance\n@author\m@ne
      \global\advance\n@collab\m@ne
      \global\@firstauthortrue
      \global\@hasabstractfalse
      \global\@prefacefalse
      \@ifundefined{RIfM@}{}{\undo@AMS}%
      \parskip 4\p@
      \open@fm \ignorespaces}
    \def\preface{\@prefacetrue}
    \def\endfrontmatter{\global\n@author=\c@author
      \global\n@collab=\c@collab \@writecount
      \global\@topnum\z@
      \ifx\@firstpage\@lastpage
        \gdef\@pagerange{\@pagenumprefix\@firstpage}
      \else
        \gdef\@pagerange{\@pagenumprefix\@firstpage--\@pagenumprefix\@lastpage}
      \fi
      \thispagestyle{copyright}%
      \if@preface \else
      \history@fmt
      \newcount\c@sv@footnote
      \global\c@sv@footnote=\c@footnote
      \if@hasabstract
        \vskip 24pt plus 6pt minus 3pt
        \hrule height 0.4pt
        \vskip 8pt
        \unvbox\t@abstract
        \unvbox\t@keyword
        \vskip 10pt
        \hrule height 0.4pt
      \fi
      \dedicated@fmt
      \vskip 18pt
      \fi
      \close@fm
      \output@glob@notes
      \global\c@footnote=\c@sv@footnote
      \global\@prefacefalse
      \global\leftskip\z@
      \global\@rightskip\z@
      \global\rightskip\@rightskip
      \global\mathsurround\sv@mathsurround
      \let\title\relax       \let\author\relax
      \let\collab\relax      \let\address\relax
      \let\frontmatter\relax \let\endfrontmatter\relax
      \let\@maketitle\relax  \let\@@maketitle\relax
      \normal@text}
    \let\maketitle\relax
    \newdimen\t@xtheight
    \splittopskip=\topskip \splitmaxdepth=\maxdepth
    \t@xtheight\textheight \advance\t@xtheight-\splittopskip
    \def\open@fm{\global\setbox\fm@box=\vbox\bgroup
      \hsize=\textwidth
      \centering
      \sv@hyphenpenalty\hyphenpenalty
      \hyphenpenalty\@M}
    \def\close@fm{\egroup
      \fm@size=\dp\fm@box \advance\fm@size by \ht\fm@box
      \@whiledim\fm@size>\t@xtheight \do{%
        \global\setbox\@tempboxa=\vsplit\fm@box to \t@xtheight
        \unvbox\@tempboxa \newpage
        \fm@size=\dp\fm@box \advance\fm@size by \ht\fm@box}
      \if@TwoColumn
        \twocolumn[\unvbox\fm@box] \@TwoColumnParms
      \else
        \unvbox\fm@box
      \fi}
    \def\output@glob@notes{\bgroup
      \the\t@glob@notes
      \egroup}
    \def\justify@off{\let\\=\@normalcr
      \leftskip\z@ \@rightskip\@flushglue \rightskip\@rightskip}
    \def\justify@on{\let\\=\@normalcr
      \leftskip\z@ \@rightskip\z@ \rightskip\@rightskip}
    \def\normal@text{\global\let\\=\@normalcr
      \global\leftskip\z@ \global\@rightskip\z@ \global\rightskip\@rightskip
      \global\parfillskip\@flushglue}
    \def\@writecount{\write\@mainaux{\string\global
      \string\@namedef{n@author@}{\the\n@author}}%
      \write\@mainaux{\string\global\string
      \@namedef{n@collab@}{\the\n@collab}}}
    \def\title{\@ifnextchar[{\@@title}{\@@title[]}}
    \def\@@title[#1]#2{%
      \beg@elem
      \title@note@fmt
      \add@tok\t@glob@notes
        {\title@note@fmt}%
      \proc@elem{title}{#2}%
      \def\title@notes{\the\t@loc@notes}%
      \title@fmt{\@title}{\title@notes}%
      \ignorespaces}
    \def\subtitle#1{%
      \beg@elem
      \proc@elem{subtitle}{#1}%
      \def\title@notes{\the\t@loc@notes}%
      \subtitle@fmt{\@subtitle}{\title@notes}%
      \ignorespaces}
    \newdimen \@logoheight \@logoheight 5pc
    \newdimen \@logowidth
    \@logowidth 30mm
    \def\title@fmt#1#2{%
      \vspace*{12pt}
      {\Large #1\,\hbox{$^{#2}$}\par}%
      \vskip 24pt
      }
    \def\subtitle@fmt#1#2{%
      {\Large #1\,\hbox{$^{#2}$}\par}}
    \def\title@note@fmt{\def\thefootnote{\fnstar{footnote}}}
    \def\author{\@ifnextchar[{\author@optarg}{\author@optarg[]}}
    \def\author@optarg[#1]#2{\stepcounter{author}%
      \beg@elem
      \@for\@tempa:=#1\do{\expandafter\add@thanksref\expandafter{\@tempa}}%
      \report@elt{author}\proc@elem{author}{#2}%
      \author@fmt{\the\c@author}{\the\t@loc@notes}{\@author}}%
    \def\author@fmt#1#2#3{\@newelemtrue
      \if@firstauthor
      \first@author \global\@firstauthorfalse \fi
      \ifnum\prev@elem=\e@author \global\@newelemfalse \fi
      \if@newelem \author@fmt@init \fi
      \edef\@tempb{#2}\ifx\@tempb\@empty
        \hbox{#3}\else
        \hbox{#3\,$^{\mathrm{#2}}$}%
      \fi}
    \def\first@author{\author@note@fmt
      \add@tok\t@glob@notes
        {\author@note@fmt\@corresp@note}}%
    \def\author@fmt@init{%
      \par
      \vskip 8pt plus 4pt minus 2pt
      \large
      \leavevmode}
    \def\and{\unskip~and~}
    \def\collab{\@ifstar{\collab@arg}{\collab@arg}}
    \let\collaboration=\collab
    \def\collab@arg#1{\stepcounter{collab}%
      \if@firstauthor \first@collab \global\@firstauthorfalse \fi
      \beg@elem
      \proc@elem{collab}{#1}%
      \collab@fmt{\the\c@collab}{\the\t@loc@notes}{\@collab}%
      \ignorespaces}
    \def\collab@fmt#1#2#3{\@newelemtrue
      \ifnum\prev@elem=\e@collab \global\@newelemfalse \fi
      \if@newelem \collab@fmt@init \fi
      \par
      {\large #3\,$^{\mathrm{#2}}$}}
    \def\first@collab{
      \collab@note@fmt
      \add@tok\t@glob@notes{\collab@note@fmt\@corresp@note}}%
    \def\collab@fmt@init{\vskip 1em}
    \def\author@note@fmt{\setcounter{footnote}{0}%
      \def\thefootnote{\xarabic{footnote}}}
    \let\collab@note@fmt=\author@note@fmt
    \def\xarabic#1{%
      \expandafter\expandafter\expandafter\ifnum\expandafter\the\@nameuse{c@#1}<0
      *\else\arabic{#1} \fi}
    \def\address{\@ifstar{\address@star}%
      {\@ifnextchar[{\address@optarg}{\address@noptarg}}}
    \def\address@optarg[#1]#2{\refstepcounter{address}%
      \beg@elem
      \report@elt{address}\proc@elem{address}{#2}%
      \address@fmt{\the\c@address}{\the\t@loc@notes}{\@address}\label{#1}%
      \ignorespaces}
    \def\address@noptarg#1{\refstepcounter{address}%
      \beg@elem
      \proc@elem{address}{#1}%
      \address@fmt{\z@}{\the\t@loc@notes}{\@address}%
      \ignorespaces}
    \def\address@star#1{%
      \beg@elem
      \proc@elem{address}{#1}%
      \address@fmt{\m@ne}{\the\t@loc@notes}{\@address}%
      \ignorespaces}
    \def\theaddress{\alph{address}}
    \def\address@fmt#1#2#3{\@newelemtrue
      \ifnum\prev@elem=\e@address \@newelemfalse \fi
      \if@newelem \address@fmt@init \fi
      \noindent \bgroup \small\it
      \ifnum#1=\z@
        #3\,$^{\mathrm{#2}}$\space%
      \else
        \ifnum#1=\m@ne
          $^{\phantom{\mathrm{\theaddress}}}$\space #3\,$^{\mathrm{#2}}$%
        \else
          $^{\mathrm{\theaddress}}$\space #3\,$^{\mathrm{#2}}$%
        \fi
      \fi
      \par \egroup}
    \def\address@fmt@init{%
      \par
      \vskip 6pt plus 3pt minus 1.5pt}
    \def\abstract{\@ifnextchar[{\@abstract}{\@abstract[]}}
    \def\@abstract[#1]{%
      \global\@hasabstracttrue
      \hyphenpenalty\sv@hyphenpenalty
      \global\setbox\t@abstract=\vbox\bgroup
      \leftskip\z@
      \@rightskip\z@ \rightskip\@rightskip \parfillskip\@flushglue
      \small
      \parindent 1em
      \noindent {\bf\abstractname}
      \vskip 0.5\@bls
      \ignorespaces}
    \def\endabstract{\par \egroup}
    \def\keyword#1{%
      \global\@hasabstracttrue
      \hyphenpenalty\sv@hyphenpenalty
      \def\sep{\unskip; }
      \def\MSC{\par\leavevmode\hbox {\it 1991 MSC:\ }}%
      \def\PACS{\par\leavevmode\hbox {\it PACS:\ }}%
      \def\JEL{\par\leavevmode\hbox {\it JEL classification:\ }}%
      \def\UK{\par\leavevmode\hbox {\it Keywords:\ }}%
      \let\CK\relax
      \global\setbox\t@keyword=\vbox\bgroup
      \small
      \parskip\z@
      \vskip 10pt plus 2pt minus 2pt
      \noindent
      \justify@off
      \UK #1%
    }
    \def\endkeyword{\par \egroup}
    \def\journal#1{\gdef\@journal{#1}}
    \def\volume#1{\gdef\@volume{#1}}       \def\@volume{0}
    \def\issue#1{\gdef\@issue{#1}}         \def\@issue{0}
    \newcount\@pubyear
    \newcount\@copyear
    \@pubyear=\number\year
    \@copyear\@pubyear \advance\@copyear-1900
    \def\pubyear#1{\global\@pubyear#1
      \global\@copyear\@pubyear \global\advance\@copyear-1900
      \ignorespaces}
    \def\firstpage#1{\def\@tempa{#1}\ifx\@tempa\@empty\else
      \gdef\@firstpage{#1}\gdef\@lastpage{#1}%
      \global\c@page=#1 \ignorespaces\fi
      }
    \def\@firstpage{1}
    \def\lastpage#1{\def\@tempa{#1}\ifx\@tempa\@empty\else
      \gdef\@lastpage{#1}\ignorespaces\fi}
    \def\@lastpage{0}
    \def\@pagerange{1--0}
    \def\date#1{\gdef\@date{#1}}                  \def\@date{\today}
    \def\aid#1{}
    \def\ssdi#1#2{}
    \def\received#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@received{#1}\fi}
      \def\@received{\@nil}
    \def\revised#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@revised{#1}\fi}
      \def\@revised{\@nil}
    \def\accepted#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@accepted{#1}\fi}
      \def\@accepted{\@nil}
    \def\communicated#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@communicated{#1}\fi}
      \def\@communicated{\@nil}
    \def\dedicated#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@dedicated{#1}\fi}
      \def\@dedicated{\@nil}
    \def\presented#1{\def\@tempa{#1}\ifx\@tempa\@empty\else\gdef\@presented{#1}\fi}
      \def\@presented{\@nil}
    \def\articletype#1{\gdef\@articletype{#1}}
      \@ifundefined{@articletype}{\def\@articletype{}}{}
    \def\received@prefix{Received~}
    \def\revised@prefix{; revised~}
    \def\accepted@prefix{; accepted~}
    \def\communicated@prefix{\\Communicated~by~}
    \def\history@prefix{}
    \def\received@postfix{}
    \def\revised@postfix{}
    \def\accepted@postfix{}
    \def\communicated@postfix{}
    \def\history@postfix{}
    \def\empty@data{\@nil}
    \def\history@fmt{%
      \bgroup
      \small
      \vskip 6pt plus 2pt minus 1pt
      \ifx\@received\empty@data \else
        \leavevmode
        \history@prefix
        \received@prefix\@received \received@postfix%
        \ifx\@revised\empty@data \else
          \revised@prefix\@revised \revised@postfix%
        \fi
        \ifx\@accepted\empty@data \else
          \accepted@prefix\@accepted \accepted@postfix%
        \fi
        \ifx\@communicated\empty@data \else
          \communicated@prefix\@communicated \communicated@postfix%
        \fi
        \history@postfix
      \fi
      \par \egroup}
    \def\dedicated@fmt{%
      \ifx\@dedicated\empty@data \else
        \vskip 4pt plus 3pt
        \normalsize\it\centering \@dedicated
        \fi}
    \def\@ialph#1{\ifcase#1\or \or \or \or \or e\or f\or g\or h\or i\or j\or
      k\or \protect\text{$\ell$}\or m\or n\or o\or p\or q\or r\or s\or t\or u\or v\or w\or x\or
      y\or z\or aa\or ab\or ac\or ad\or ae\or af\or ag\or ah\or ai\or aj\or
      ak\or a\protect\text{$\ell$}\or am\or an\or ao\or ap\or aq\or ar\or as\or at\or au\or av\or
      aw\or ay\or az\or ba\or bb\or bc\or bd\or be\or bf\or bg\or bh\or bi\or
      bj\or bk\or b\protect\text{$\ell$}\or bm\or bn\or bo\or bp\or bq\or br\or bs\or bt\or
      bu\or bw\or bx\or by\or bz\or ca\or cb\or cc\or cd\or ce\or cf\or cg\or
      ch\or ci\or cj\or ck\or c\protect\text{$\ell$}\or cm\or cn\or co\or cp\or cq\or cr\or
      cs\or ct\or cu\or cw\or cx\or cy\or cz\else\@ctrerr\fi}
    \def\fnstar#1{\@fnstar{\@nameuse{c@#1}}}
    \def\@fnstar#1{\ifcase#1\or
        \hbox{$\star$}\or
        \hbox{$\star\star$}\or
        \hbox{$\star\star\star$}\or
        \hbox{$\star\star\star\star$}\or
        \hbox{$\star\star\star\star\star$}\or
        \hbox{$\star\star\star\star\star\star$}
      \else
        \@ctrerr
      \fi
      \relax}
    \mark{{}{}}
    \def\ps@plain{\let\@mkboth\@gobbletwo
     \def\@oddhead{}%
     \def\@evenhead{}%
     \def\@oddfoot{\hfil {\rm\thepage} \hfil}%
     \let\@evenfoot\@oddfoot}
    \def\@copyright{\@issn/\the\@copyear/\$\@price\ $\copyright$\ \the\@pubyear\
      Elsevier Science B.V. All rights reserved}
    \def\@jou@vol@pag{\@journal\ \@volume\ (\the\@pubyear)\ \@pagerange}
    \let\@j@v@p\@jou@vol@pag
    \let\@@j@v@p\@jou@vol@pag
    \def\sectionmark#1{}
    \def\subsectionmark#1{}
    \def\ps@copyright{\let\@mkboth\@gobbletwo
      \def\@oddhead{}%
      \let\@evenhead\@oddhead
      \def\@oddfoot{\small\sl
        \def\@tempa{0}
        \ifx\@volume\@tempa
          Preprint submitted to \@journal\hfil\@date\/%
        \else
          Article published in \@jou@vol@pag\hfil\hbox{}\fi}%
      \let\@evenfoot\@oddfoot
    }
    \let\ps@noissn\ps@empty
    \let\ps@headings\ps@plain
    \def\today{\number\day\space\ifcase\month\or
      January\or February\or March\or April\or May\or June\or
      July\or August\or September\or October\or November\or December\fi
      \space\number\year}
    \if@nfss \relax \else
      \def\mathrm#1{{\rm #1}}
    \fi
    \def\nuc#1#2{\relax\ifmmode{}^{#1}{\protect\text{#2}}\else${}^{#1}$#2\fi}
    \def\itnuc#1#2{\setbox\@tempboxa=\hbox{\scriptsize\it #1}
      \def\@tempa{{}^{\box\@tempboxa}\!\protect\text{\it #2}}\relax
      \ifmmode \@tempa \else $\@tempa$\fi}
    \let\old@vec\vec
    \def\pol#1{\old@vec{#1}}
    \def\@bfvec#1{\boldsymbol{#1}}
    \def\@pmbfvec#1{\pmb{#1}}
    \def\undo@AMS{\global\let\vec\@bfvec}
    \def\half{{\textstyle {1\over2}}}
    \def\threehalf{{\textstyle {3\over2}}}
    \def\quart{{\textstyle {1\over4}}}
    \def\d{\,\mathrm{d}}
    \def\e{\mathop{\mathrm{e}}\nolimits}
    \def\int{\intop}
    \def\oint{\ointop}
    \newbox\slashbox \setbox\slashbox=\hbox{$/$}
    \newbox\Slashbox \setbox\Slashbox=\hbox{\large$/$}
    \def\pFMslash#1{\setbox\@tempboxa=\hbox{$#1$}
      \@tempdima=0.5\wd\slashbox \advance\@tempdima 0.5\wd\@tempboxa
      \copy\slashbox \kern-\@tempdima \box\@tempboxa}
    \def\pFMSlash#1{\setbox\@tempboxa=\hbox{$#1$}
      \@tempdima=0.5\wd\Slashbox \advance\@tempdima 0.5\wd\@tempboxa
      \copy\Slashbox \kern-\@tempdima \box\@tempboxa}
    \def\FMslash{\protect\pFMslash}
    \def\FMSlash{\protect\pFMSlash}
    \mathchardef\Gamma="0000
    \mathchardef\Delta="0001
    \mathchardef\Theta="0002
    \mathchardef\Lambda="0003
    \mathchardef\Xi="0004
    \mathchardef\Pi="0005
    \mathchardef\Sigma="0006
    \mathchardef\Upsilon="0007
    \mathchardef\Phi="0008
    \mathchardef\Psi="0009
    \mathchardef\Omega="000A
    \mathchardef\varGamma="0100
    \mathchardef\varDelta="0101
    \mathchardef\varTheta="0102
    \mathchardef\varLambda="0103
    \mathchardef\varXi="0104
    \mathchardef\varPi="0105
    \mathchardef\varSigma="0106
    \mathchardef\varUpsilon="0107
    \mathchardef\varPhi="0108
    \mathchardef\varPsi="0109
    \mathchardef\varOmega="010A
    \if@nfss
      \def\Cset{\Bbb{C}}
      \def\Hset{\Bbb{H}}
      \def\Nset{\Bbb{N}}
      \def\Qset{\Bbb{Q}}
      \def\Rset{\Bbb{R}}
      \def\Zset{\Bbb{Z}}
    \fi
    \ps@headings
    \pagenumbering{arabic}
    \def\thepage{\@pagenumprefix\arabic{page}}
    \endinput