https://mappingthelives.org/bio/46fd3a37-968e-401c-8e7e-54dac737eff9?language=en
https://www.joodsmonument.nl/nl/page/190299/alfred-richard-proskauer
https://www.oorlogsbronnen.nl/tijdlijn/65fd9323-a8e0-444a-be8b-d024e122e805
Alfred Richard Proskauer (1908 - 1945) - Genealogy
https://archief.amsterdam/indexen/deeds/9853341a-14df-56a3-e053-b784100ade19?person=9853341a-14e0-56a3-e053-b784100ade19
https://museenkoeln.de/ns-dokumentationszentrum/default.aspx?sfrom=2923&s=2922&id=37059&ort=Auschwitz