Marianne Velleman, daughter of Joseph Velleman and Fanny Manheim, had two other sisters: Louise and Clara, who suvived the Holocaust. City Archive of Amsterdam, archive card of Joseph Velleman.
In addition, a Jokos file (number 20709) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.