diff -r 1888e3cb8048 -r 262572d90bc6 src/HOL/Multivariate_Analysis/Derivative.thy
--- a/src/HOL/Multivariate_Analysis/Derivative.thy	Sun Nov 02 17:06:05 2014 +0100
+++ b/src/HOL/Multivariate_Analysis/Derivative.thy	Sun Nov 02 17:09:04 2014 +0100
@@ -3,7 +3,7 @@
     Author:     Robert Himmelmann, TU Muenchen (translation from HOL Light)
 *)
 
-header {* Multivariate calculus in Euclidean space *}
+section {* Multivariate calculus in Euclidean space *}
 
 theory Derivative
 imports Brouwer_Fixpoint Operator_Norm