Index: tol/btol/set_type/set.cpp
===================================================================
--- tol/btol/set_type/set.cpp	(revision ba8b08f43e55760725d6eb31634b3bae257f6f1b)
+++ tol/btol/set_type/set.cpp	(revision 652b5b0b9561e7df9a4ecfe8e4def84e0eaf54d9)
@@ -761,6 +761,12 @@
 //--------------------------------------------------------------------
 {
-  BSet res  = (*this);
-  for(BInt n=1; n<=set.Card(); n++)
+  int n;
+  BSet res;
+  res.PrepareStore(Card()+set.Card());
+  for(n=0; n<array_.Size(); n++)
+  { 
+    res.AddElement(array_[n]); 
+  }
+  for(n=1; n<=set.Card(); n++)
   { 
     if(!Includes(set[n]))