diff --git a/src/lagrangian/intermediate/submodels/Kinematic/CollisionModel/PairCollision/WallModel/WallModel/WallModel.H b/src/lagrangian/intermediate/submodels/Kinematic/CollisionModel/PairCollision/WallModel/WallModel/WallModel.H
index 3d6a6cfcf12bcaacc2c68780a3fee9fb7d866e05..729a0c8bdf8746da09ce674e238e9e88d7e8275c 100644
--- a/src/lagrangian/intermediate/submodels/Kinematic/CollisionModel/PairCollision/WallModel/WallModel/WallModel.H
+++ b/src/lagrangian/intermediate/submodels/Kinematic/CollisionModel/PairCollision/WallModel/WallModel/WallModel.H
@@ -39,6 +39,7 @@ SourceFiles
 #include "IOdictionary.H"
 #include "autoPtr.H"
 #include "runTimeSelectionTables.H"
+#include "WallSiteData.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //