Lemma l13_10_aux2 : forall O A B la lla lb llb, Col O A B -> Q_Cong la -> Q_Cong lla -> Q_Cong lb -> Q_Cong llb -> la O A -> lla O A -> lb O B -> llb O B -> A <> O -> B <> O -> exists a, Q_CongA_Acute a /\ Lcos lla la a /\ Lcos llb lb a.