\hoffset=-.25  truein \voffset=-0.5 truein \oddsidemargin=0.0 truein
\topmargin=-.15 truein \textwidth=7.0 truein \textheight=8.91 truein

%some convenient definitions.

\def\cl{\centerline} 
\def\mma{{\it Mathematica\/}} 
\def\eg{{\it e.g.\/}} 
\def\etc{{\it etc.\/}} 
\def\ie{{\it i.e.\/}}
\def\ni{\noindent}