Jacob Fonteijn was a son of Abraham Fonteijn and Sara Jacobs. Jacob's second marriage was to Louise Drukker. From his first marriage Abraham (1911) was born.
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According to a list with shops of Jewish owners, compiled by the Amsterdam police in 1940, Jacob Fonteijn had a tobacco shop, address: Plantage Kerklaan 28 in Amsterdam.
Abstracts of the police archives which are currently at the Amsterdam municipal archives