https://data.jck.nl/page/aggregation/jhm-documenten/D017801
https://www.maxvandam.info/humo-gen/family/1/F57775?main_person=I153593
https://archief.amsterdam/indexen/deeds/56ce2863-c16e-4b05-907c-2cf355c9e749?person=99e87e2e-aca4-2bb2-e053-b784100a6a2e
Fate mother and brother: https://www.joodsmonument.nl/en/page/225176/flora-de-jong-van-lier-adler
Flora Adler (1871 - 1943) - Genealogy