Jacob Winnik was a son of Salomon Winnik and Marianne Swaalep. He married in Amsterdam on 19 February 1942 to Hendrika Groenteman, daugther of Barend Groenteman and Vogeltje de Rood.
City Archive of Amsterdam, archive cards of Jacob Winnik and Hendrika Groenteman.
In addition, Jokos files (numbers 15631, 15241) on this family or other family members are at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.