https://www.joodsmonument.nl/nl/page/207116/fritz-siegfried-loewenberg
https://www.mappingthelives.org/bio/2b949007-05f6-4ae3-8b14-510a359be6fb
Dr. Fritz Siegfried Löwenberg (1901 - 1942) - Genealogy (geni.com)
https://meta-studies.net/genealogy/PS05/PS05_222.HTML
https://archief.amsterdam/indexen/deeds/985333f2-2aa6-56a3-e053-b784100ade19?person=985333f2-2aa7-56a3-e053-b784100ade19