diff --git a/externals/Makefile b/externals/Makefile
index 057881d1ef23dee5690f3748c5709b2aac7f7e22..6e6826ac6d2a1c44862cfbf9b17ff6d4b1da3868 100644
--- a/externals/Makefile
+++ b/externals/Makefile
@@ -1203,7 +1203,7 @@ moocow_clean:
 	$(MAKE) -C $(externals_src)/moocow/extended distclean
 	-rm -f -- $(MOOCOW_DIR)/*.bak
 	-rm -f -- $(MOOCOW_DIR)/*.*~
-
+	cp -f $(MOOCOW_DIR)/../gfsm/gfsm/src/libgfsm/default/* $(MOOCOW_DIR)/../gfsm/gfsm/src/libgfsm/ 
 
 
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