| 1. | In 1970, Maetzl was a founder member, with Günter Pichler, Hatto Beyerle and Valentin Erben, of the Alban Berg Quartet, in which he played second violin; he remained with the quartet until 1978. En 1970 Maetzl a été membre fondateur, avec Günter Pichler, Hatto Beyerle et Valentin Erben, du Quatuor Alban Berg, où il tenait le poste de second violon. |