https://www.dutchjewry.org/genealogy/ff2/63.shtml
https://www.joodsmonument.nl/nl/page/468571/partner-of-simon-frankfort-and-his-family
Theresia Frankfort (Polak) (1882 - 1947) - Genealogy (geni.com)
https://www.maxvandam.info/humo-gen/family/1/F66422?main_person=I175063