--- a/src/HOL/Unix/document/root.tex Tue Mar 09 20:00:44 2021 +0100
+++ b/src/HOL/Unix/document/root.tex Tue Mar 09 21:11:05 2021 +0100
@@ -1,5 +1,5 @@
-
\documentclass[11pt,a4paper]{article}
+\usepackage[T1]{fontenc}
\usepackage{isabelle,isabellesym,pdfsetup}
%for best-style documents ...