diff --git a/exercises/exercise-basic/injection2p2cproblem.hh b/exercises/exercise-basic/injection2p2cproblem.hh
index bade4fc295c697004b4a2ad4e12d70d82e607708..81a593983d91023322836cb911ac75d2683cca0b 100644
--- a/exercises/exercise-basic/injection2p2cproblem.hh
+++ b/exercises/exercise-basic/injection2p2cproblem.hh
@@ -27,6 +27,7 @@
 
 #include <dumux/common/properties.hh>
 #include <dumux/porousmediumflow/problem.hh>
+#include <dumux/material/binarycoefficients/h2o_n2.hh>
 
 namespace Dumux {