Joel Zwaab was a son of Emanuel Zwaab and Duijfje Komkommer. He married 1 July 1915 in Amsterdam to Rozette Blog, a daughter of Gompel Blog and Netje Visschraper. The had a son Emanuel.
City Archive of Amsterdam, archive card of Emanuel Zwaag and family registration card of Joel Zwaab from the Munic…
In addition, a Jokos file (number 52936) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.