diff --git a/apps/openmw/mwworld/livecellref.cpp b/apps/openmw/mwworld/livecellref.cpp
index 0f83cd9c2..32830b5fb 100644
--- a/apps/openmw/mwworld/livecellref.cpp
+++ b/apps/openmw/mwworld/livecellref.cpp
@@ -11,7 +11,7 @@
 #include "class.hpp"
 #include "esmstore.hpp"
 
-MWWorld::LiveCellRefBase::LiveCellRefBase(std::string type, const ESM::CellRef &cref)
+MWWorld::LiveCellRefBase::LiveCellRefBase(const std::string& type, const ESM::CellRef &cref)
   : mClass(&Class::get(type)), mRef(cref), mData(cref)
 {
 }
diff --git a/apps/openmw/mwworld/livecellref.hpp b/apps/openmw/mwworld/livecellref.hpp
index 3994d8a24..2631f513f 100644
--- a/apps/openmw/mwworld/livecellref.hpp
+++ b/apps/openmw/mwworld/livecellref.hpp
@@ -31,7 +31,7 @@ namespace MWWorld
         /** runtime-data */
         RefData mData;
 
-        LiveCellRefBase(std::string type, const ESM::CellRef &cref=ESM::CellRef());
+        LiveCellRefBase(const std::string& type, const ESM::CellRef &cref=ESM::CellRef());
         /* Need this for the class to be recognized as polymorphic */
         virtual ~LiveCellRefBase() { }