Leonardus Gazan was a daughter of Izak Gazan and Frederika van Oss.
Haags Gemeentearchief, overlijdensakte Leonardus Gazan
A document dated 1942 reports that Leonardus Gazan left Middelharnis for Rotterdam in 1896.
Jewish Historical Museum, Documents collection, inv.nr 3808
Leonardus Gazan and Rebecca Velleman had a daughter Frederika.
Haags Gemeentearchief, gezinskaart Leonardus Gazan
In addition, a Jokos file (number 38230) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.