Hartog van Beetz, a confectioner by trade, was married to Dina Waterman. He served as a witness at the marriage of his niece Sientje Waas-Waterman. The marriage was performed at Westerbork transit camp on 4 october 1943. He signed the marriage certificate.
Record of marriage certificates of the Westerbork municipality, currently at the archives of Gemeente Midden-Drenthe in Beilen
In addition, a Jokos file (number 15507) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.