The Police Commissioner of Delft requested on behalf of the Sicherheitspolizei in The Hague that Jacob de Groot, shopkeeper, and his wife Sophia de Groot-van Hasselt, both living in Delft, be located, detained and brought to trial. They were suspected of having changed their place of residence without the required authorization. This description referred to Jews who had gone into hiding.
Algemeen Politieblad nr 38, 24 September 1942, 1087, notice 2061
In addition, a Jokos file (number 15549) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.