diff --git a/lemon/dfs.h b/lemon/dfs.h
--- a/lemon/dfs.h
+++ b/lemon/dfs.h
@@ -565,7 +565,7 @@
     ///added with addSource() before using this function.
     void start(Node t)
     {
-      while ( !emptyQueue() && G->target(_stack[_stack_head])!=t )
+      while ( !emptyQueue() && !(*_reached)[t] )
         processNextArc();
     }
 
@@ -1512,7 +1512,7 @@
     /// \pre init() must be called and a root node should be added
     /// with addSource() before using this function.
     void start(Node t) {
-      while ( !emptyQueue() && _digraph->target(_stack[_stack_head]) != t )
+      while ( !emptyQueue() && !(*_reached)[t] )
         processNextArc();
     }