diff --git a/Miscellany/doc/Miscellany/CGAL/Union_find.h b/Miscellany/doc/Miscellany/CGAL/Union_find.h
index 61f968d6309..4d1d5eccecf 100644
--- a/Miscellany/doc/Miscellany/CGAL/Union_find.h
+++ b/Miscellany/doc/Miscellany/CGAL/Union_find.h
@@ -107,7 +107,8 @@ handle push_back(const T& x) ;
 
 /*! 
 insert 
-the range of values referenced by `[first,beyond)`. \require value type of `Forward_iterator` is `T`. 
+the range of values referenced by `[first,beyond)`. 
+\requires value type of `Forward_iterator` is `T`. 
 */ 
 template <class Forward_iterator> void 
 insert(Forward_iterator first, Forward_iterator beyond) ;