See for more information on this family:
J. Blom, Nooit meer naar huis. Mijn ontsnapping uit de Hollandsche Schouwburg (Laren 2008)
In addition, a Jokos file (number 53782) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.
According to a list with shops of Jewish owners, compiled by the Amsterdam police in 1940…