"783.1242" . "4042" . "783.12 |c Duetten (verschillende zangstemmen) |d Duets (different singing voices)" . "4042 782.42 |c Liederen |d Songs 783.12 |c Duetten (verschillende zangstemmen) |d Duets (different singing voices) 783.1242" . . . "4042" . . "782.42 |c Liederen |d Songs" . .