--- a/Slides/Slides5.thy	Wed Aug 29 13:09:36 2012 +0000
+++ b/Slides/Slides5.thy	Thu Aug 30 08:30:57 2012 +0000
@@ -1165,9 +1165,9 @@
   derivatives refine \smath{x \approx_{{\cal{L}}(r)} y}\bigskip
   \begin{center}
   \only<2>{\mbox{\hspace{-22mm}}\smath{{\cal{L}}(\text{ders}~x~r) = {\cal{L}}(\text{ders}~y~r)
-    \Longleftrightarrow x \approx_{L(r)} y}}
+    \Longleftrightarrow x \approx_{{\cal{L}}(r)} y}}
   \only<3>{\mbox{\hspace{-22mm}}\smath{\text{ders}~x~r = \text{ders}~y~r 
-   \Longrightarrow x \approx_{L(r)} y}}
+   \Longrightarrow x \approx_{{\cal{L}}(r)} y}}
   \end{center}\bigskip
   \
   \smath{\text{finite}(\text{ders}~A~r)}, but only modulo ACI