David de Wolff was a son of Abraham de Wolff and Goudtje de Vries.
Regional Archive of Leiden.
David de Wolff married to Rebecca de Wolff in Amsterdam on 28 August 1908.
Municipal Archive, family registration card of David de Wolff.
In addition, a Jokos file (number 5015) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.