Source of acquisition is the Nederlands Instituut voor Oorlogsdocumentatie, NIOD, (Netherlands Institute for War Documentation), Bloch Brothers, Fond 293. The collection was found on the annex of their former company address by accident in 1997 and was transferred to NIOD and has been successively restored and inventoried. It is not a complete collection, but a unique source illuminating Jewish emigration and Jewish refugee help. The United States Holocaust Memorial Museum Archives received the collection via the United States Holocaust Museum International Archives Program in January 2010.