Ltac CopR :=
 let tpoint := constr:(Tpoint) in
 let col := constr:(Col) in
 let cop := constr:(Coplanar) in
   assert_ncols; Cop_refl tpoint col cop.

Lemma l10_4_spec : forall A B P P', ReflectL P P' A B -> ReflectL P' P A B.