. "Source of acquisition the Żydowski Instytut Historyczny im. Emanuela Ringelbluma (ŻIH), Sygn. 236. ŻIH purchased the collection from Bogumiła Dłużek on 5 January, 2004. The United States Holocaust Memorial Museum Archives received the collection from ŻIH via the United States Holocaust Memorial Museum International Programs Division in Sep. 2012."@en . .