Section MESSAGE.
(* as formulated by Jean *)
(* As I need it in my proof *)
(* The proof is long and very boring, but it is a simple case analysis.  Could it be possible to simplify it? *)

Lemma no_copy_to_owner :
forall c0 : Config,
legal c0 -> forall s1 : Site, ~ In_queue Message copy (bm c0 s1 owner).