diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index 45353e2ee..84b5a48fb 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -38,6 +38,7 @@
 #include <boost/algorithm/string.hpp>
 
 using namespace std;
+using namespace solidity;
 using namespace solidity::langutil;
 using namespace solidity::frontend;