Sippora van Gelderen was a daughter of Mozes van Gelderen and Catharina Polak. She married Benjamin de Jong in 1931 in Amsterdam. She was a fröbel teacher.
Stadsarchief Amsterdam, archiefkaart Sippora van Gelderen
In addition, a Jokos file (number 10571) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.The Jokos file reveals that a claim was lodged for compensation for valuables surrendered to the Lippmann-Rosenthal looting …