1% extra.sty : Isabelle Manual extra macros for non-Springer version
2%
3\typeout{Document Style extra. Released 17/2/94, version of 22/8/00}
4
5%%Euro-style date: 20 September 1955
6\def\today{\number\day\space\ifcase\month\or
7January\or February\or March\or April\or May\or June\or
8July\or August\or September\or October\or November\or December\fi
9\space\number\year}
10
11%%%Put first chapter on odd page, with arabic numbering; like \cleardoublepage
12\newcommand\clearfirst{\clearpage\ifodd\c@page\else
13    \hbox{}\newpage\if@twocolumn\hbox{}\newpage\fi\fi
14    \pagenumbering{arabic}}
15
16%%%Ruled chapter headings 
17\def\@rulehead#1{\hrule height1pt \vskip 14pt \Huge \bf 
18   #1 \vskip 14pt\hrule height1pt}
19\def\@makechapterhead#1{ { \parindent 0pt 
20 \ifnum\c@secnumdepth >\m@ne \raggedleft\large\bf\@chapapp{} \thechapter \par 
21 \vskip 20pt \fi \raggedright \@rulehead{#1} \par \nobreak \vskip 40pt } }
22
23\def\@makeschapterhead#1{ { \parindent 0pt \raggedright 
24 \@rulehead{#1} \par \nobreak \vskip 40pt } }
25
26