Structure > UA : Type :=
{UA_ob : A; UA_mor : b --> G UA_ob; Prf_IsUA :> IsUA UA_mor}.
(*** rewrite rules ***)

Lemma UA_unic :
forall (u : UA) (a' : A) (f : b --> G a') (g : UA_ob u --> a'),
UA_mor u o FMor G g =_S f -> g =_S UA_diese u f.