Cita libro |nome=Henry Burnand |cognome=Garland |nome2=Henry |cognome2=Garland |nome3=Mary |cognome3=Garland |titolo=The Oxford Companion to German Literature |anno=1986 |url=https://archive.org/details/oxfordcompaniont0000garl |data=1997 |editore=Oxford University Press |capitolo=Piontek, Heinz |ISBN=978-0-19-815896-7
Cita libro |nome=Raymond |cognome=Furness |nome2=Malcolm |cognome2=Humble |titolo=A Companion to Twentieth-Century German Literature |anno=1990 |url=https://archive.org/details/companiontotwent00ogra |data=2003|editore=Routledge |capitolo=Piontek, Heinz|ISBN=978-1-134-74764-1
