src/Doc/Main/document/root.tex

prefer lmodern, which produces scalable T1 fonts even with Debian-ized TeXLive;

\documentclass[12pt,a4paper]{article}
\usepackage{lmodern}
\usepackage[T1]{fontenc}

\oddsidemargin=4.6mm
\evensidemargin=4.6mm
\textwidth=150mm
\topmargin=4.6mm
\headheight=0mm
\headsep=0mm
\textheight=234mm

\usepackage{isabelle,isabellesym}
\usepackage{amssymb}
\usepackage[only,bigsqcap]{stmaryrd}

% this should be the last package used
\usepackage{pdfsetup}

% urls in roman style, theory text in math-similar italics, with literal underscore
\urlstyle{rm}
\isabellestyle{literal}

% for uniform font size
\renewcommand{\isastyle}{\isastyleminor}

\parindent 0pt\parskip 0.5ex

\usepackage{supertabular}

\begin{document}

\title{What's in Main}
\author{Tobias Nipkow}
\date{\today}
\maketitle

\input{Main_Doc.tex}

\end{document}