\documentclass[11pt,a4paper]{article}
\usepackage{graphicx,isabelle,isabellesym}
\usepackage{amssymb}
\usepackage[english]{babel}
% this should be the last package used
\usepackage{pdfsetup}
% proper setup for best-style documents
\urlstyle{rm}
\isabellestyle{it}
\begin{document}
\title{ZF}
\author{Lawrence C Paulson and others}
\maketitle
\tableofcontents
\begin{center}
\includegraphics[width=\textwidth,height=\textheight,keepaspectratio]{session_graph}
\end{center}
\newpage
\renewcommand{\isamarkupheader}[1]%
{\section{\isabellecontext: #1}\markright{THEORY~``\isabellecontext''}}
\parindent 0pt\parskip 0.5ex
% include generated text of all theories
\input{session}
%\bibliographystyle{abbrv}
%\bibliography{root}
\end{document}