Jewish Historical Institute in Warsaw, Holocaust Survivor Testimonies (coll. 301), Marta Klein Testimony (301/12). Original in Polish.
Testimony of Marta Klein on the actions against Jews in Vilnius and Białystok and deportations to Treblinka, her escape en route to the camp, her rescue by a Pole, Czuliński, and the arrest of her son and his protector after their betrayal.
The Wiener Library for the Study of the Holocaust and Genocide, Persecution of Jews in Poland: reports and statements (coll. 532), 107. Original in Yiddish.
A long, very detailed report by a 38-year-old female social activist about the situation of Jews in Łódź (and surrounding towns) in the first months under German occupation. She left Łódź on December 30, 1939.