--- a/src/HOL/Library/Sum_of_Squares.thy Wed Jun 17 10:57:11 2015 +0200
+++ b/src/HOL/Library/Sum_of_Squares.thy Wed Jun 17 11:03:05 2015 +0200
@@ -3,8 +3,8 @@
Author: Philipp Meyer, TU Muenchen
*)
-section {* A decision procedure for universal multivariate real arithmetic
- with addition, multiplication and ordering using semidefinite programming *}
+section \<open>A decision procedure for universal multivariate real arithmetic
+ with addition, multiplication and ordering using semidefinite programming\<close>
theory Sum_of_Squares
imports Complex_Main