--- a/doc-src/TutorialI/Types/types.tex Wed Oct 31 15:10:34 2007 +0100
+++ b/doc-src/TutorialI/Types/types.tex Thu Nov 01 13:44:44 2007 +0100
@@ -43,6 +43,14 @@
axioms of $C$ are also provable in $D$. We introduce these concepts
by means of a running example, ordering relations.
+\begin{warn}
+The material in this section describes a low-level approach to type classes.
+It is recommended to use the new \isacommand{class} command instead.
+For details see the appropriate tutorial~\cite{isabelle-classes} and the
+related article~\cite{Haftmann-Wenzel:2006:classes}.
+\end{warn}
+
+
\subsection{Overloading}
\label{sec:overloading}
\index{overloading|(}