Section PROD'.
Variable A : Type.
Variable J_A: Join A.
Variable saA : Perm_alg A.
Variable B: Type.
Variable J_B: Join B.
Variable saB : Perm_alg B.
Variable agB : ageable B.
Variable asb : Age_alg B.

Lemma joins_fashionR {A}  {JA: Join A}{PA: Perm_alg A}{agA: ageable A}{XA: Age_alg A} : forall x y,
joins x y -> fashionR x y.