diff --git a/src/Makefile.am b/src/Makefile.am
index 573e51ddc00394a27f5b34bb29252e02a25a9401..16551446d96110db9194657575b89a4502217eae 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -48,9 +48,9 @@ noinst_HEADERS = approx_math.h atomic.h cycle.h error.h inline.h kernel.h vector
 		 runner_doiact.h runner_doiact_grav.h units.h intrinsics.h \
 		 hydro.h hydro_io.h gravity.h \
 		 gravity/Default/gravity.h gravity/Default/runner_iact_grav.h \
-		 gravity/Default/gravity_part.h
+		 gravity/Default/gravity_part.h \
 		 hydro/Minimal/hydro.h hydro/Minimal/hydro_iact.h hydro/Minimal/hydro_io.h \
-                 hydro/Minimal/hydro_debug.h hydro/Minimal/hydro_part.h
+                 hydro/Minimal/hydro_debug.h hydro/Minimal/hydro_part.h \
 		 hydro/Default/hydro.h hydro/Default/hydro_iact.h hydro/Default/hydro_io.h \
                  hydro/Default/hydro_debug.h hydro/Default/hydro_part.h \
 		 hydro/Gadget2/hydro.h hydro/Gadget2/hydro_iact.h hydro/Gadget2/hydro_io.h \