diff --git a/src/HumidAirProp.cpp b/src/HumidAirProp.cpp
index 9f19db26..311ee1ba 100644
--- a/src/HumidAirProp.cpp
+++ b/src/HumidAirProp.cpp
@@ -21,7 +21,7 @@
 #include <string.h>
 #include <iostream>
 #include <list>
-#include "IF97.h"
+#include "externals/IF97/IF97.h"
 
 /// This is a stub overload to help with all the strcmp calls below and avoid needing to rewrite all of them
 std::size_t strcmp(const std::string &s, const std::string &e){