diff -r c94db1a96f4e -r 6b0b6b471855 doc-src/TutorialI/Datatype/document/ABexpr.tex
--- a/doc-src/TutorialI/Datatype/document/ABexpr.tex	Thu Aug 17 21:07:25 2000 +0200
+++ b/doc-src/TutorialI/Datatype/document/ABexpr.tex	Fri Aug 18 10:34:08 2000 +0200
@@ -102,7 +102,7 @@
 \end{ttbox}
 
 \begin{exercise}
-  Define a function \isa{norma} of type \isa{'a\ aexp\ {\isasymRightarrow}\ 'a\ aexp} that
+  Define a function \isa{norma} of type \isa{\mbox{'a}\ aexp\ {\isasymRightarrow}\ \mbox{'a}\ aexp} that
   replaces \isa{IF}s with complex boolean conditions by nested
   \isa{IF}s where each condition is a \isa{Less} --- \isa{And} and
   \isa{Neg} should be eliminated completely. Prove that \isa{norma}