Joseph Nikkelsberg was a son of Abraham Nikkelsberg and Anna Salomons. He married in Amsterdam on 27 December 1928 to Roselina Speijer. City Archive of Amsterdam, archive card of Abraham Nikkelsberg.
In addition, a Jokos file (number 50478) 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 bank (L-claim, number 8836/12967).