diff -r 9537bf1c4853 -r 5b7a9633cfa8 src/HOL/Old_Number_Theory/Fib.thy
--- a/src/HOL/Old_Number_Theory/Fib.thy	Sun Nov 02 18:21:14 2014 +0100
+++ b/src/HOL/Old_Number_Theory/Fib.thy	Sun Nov 02 18:21:45 2014 +0100
@@ -3,7 +3,7 @@
     Copyright   1997  University of Cambridge
 *)
 
-header {* The Fibonacci function *}
+section {* The Fibonacci function *}
 
 theory Fib
 imports Primes