diff --git a/include/core/common/wolf.h b/include/core/common/wolf.h
index d4976b53ee5060fedaee9432f8243187fe71db6e..6587cf5ea242396a40f29feb07bc0828271d8f4a 100644
--- a/include/core/common/wolf.h
+++ b/include/core/common/wolf.h
@@ -108,7 +108,7 @@ namespace wolf {
 
 /// State of nodes containing several state blocks
 typedef std::unordered_map<std::string, Eigen::VectorXd> State;
-typedef std::list<std::string> StateStructure;
+typedef std::string StateStructure;
 
 
 //////////////////////////////////////////////////////////