Judith Pach was a daughter of the couple Mozes Pach, who already died in 1925 and Esther Spanjar. Genlias and City Archive of Amsterdam, archive card of Esther Spanjar.
In addition, a Jokos file (number 12058) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.