diff -r 82a8f2bc5758 -r 5adcef1d7bcc src/work/marci/bfs_iterator.h
--- a/src/work/marci/bfs_iterator.h	Thu May 06 17:45:12 2004 +0000
+++ b/src/work/marci/bfs_iterator.h	Thu May 06 18:07:45 2004 +0000
@@ -6,6 +6,8 @@
 #include <stack>
 #include <utility>
 
+#include <hugo/invalid.h>
+
 namespace hugo {
 
   template <typename Graph, /*typename OutEdgeIt,*/