Grietje Veerejong was a daughter of Benjamin Moses Veerejong and Henriëtte Leefson. She married Isaäc Polk in 1914 in Amsterdam. Stadsarchief Amsterdam, archiefkaart Grietje Veerejong
In addition, a Jokos file (number 18006) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.