diff -r 7e51c9f3d5a0 -r a5f86aed785b doc-src/TutorialI/Misc/document/fakenat.tex
--- a/doc-src/TutorialI/Misc/document/fakenat.tex	Tue Aug 29 15:13:10 2000 +0200
+++ b/doc-src/TutorialI/Misc/document/fakenat.tex	Tue Aug 29 15:43:29 2000 +0200
@@ -1,11 +1,12 @@
-\begin{isabelle}%
+%
+\begin{isabellebody}%
 %
 \begin{isamarkuptext}%
 \noindent
 The type \isaindexbold{nat}\index{*0|bold}\index{*Suc|bold} of natural
 numbers is predefined and behaves like%
 \end{isamarkuptext}%
-\isacommand{datatype}\ nat\ {\isacharequal}\ \isadigit{0}\ {\isacharbar}\ Suc\ nat\end{isabelle}%
+\isacommand{datatype}\ nat\ {\isacharequal}\ \isadigit{0}\ {\isacharbar}\ Suc\ nat\end{isabellebody}%
 %%% Local Variables:
 %%% mode: latex
 %%% TeX-master: "root"