David Boeken and Saartje van Oosten married in 1913 in Amsterdam.
Stadsarchief Amsterdam, archiefkaart Saartje van Oosten
In addition, a Jokos file (number 15597) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.The Jokos file reveals that a claim was lodged for compensation for valuables surrendered to the Lippmann-Rosenthal looting bank (L-claim, number 1228 / 11859).