diff --git a/packages/CLPBN/clpbn/ve.yap b/packages/CLPBN/clpbn/ve.yap
index fd221dd41..e81898fe6 100644
--- a/packages/CLPBN/clpbn/ve.yap
+++ b/packages/CLPBN/clpbn/ve.yap
@@ -64,7 +64,8 @@
 :- use_module(library(lists),
 		[member/2,
 		 append/3,
-		 delete/3
+		 delete/3,
+		 sum_list/2
 		]).
 
 :- use_module(library(maplist)).
diff --git a/packages/bdd/bdd.yap b/packages/bdd/bdd.yap
index fa5163b10..8b1331a54 100644
--- a/packages/bdd/bdd.yap
+++ b/packages/bdd/bdd.yap
@@ -1,5 +1,6 @@
 
-:- module(bdd, [bdd_new/2,
+:- module(bdd, [
+	bdd_new/2,
 	bdd_new/3,
 	bdd_from_list/3,
 	mtbdd_new/2,