Addition

Izak Colthof and his family

Izak Colthof and Jenny Hammelburg also had a daughter Betje.
Stadsarchief Amsterdam, archiefkaart Betje Colthof

In addition, a Jokos file (number 32091) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.