Benjamin Polak was deported to Sobibor in June 1943 from Vught via Westerbork on the so-called children's transport. He was 6 years old when he died. J. de Moei, Joodse kinderen in het kamp Vught (Vught 1999) 63
In addition, a Jokos file (number 8290) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.