Holocaust survivor Minna Aspler -- who spent time in the Warsaw Ghetto -- recalls the personality of Emanuel Ringelblum, who had been her history teacher. Ringelblum went on to lead a clandestine effort with other Warsaw Ghetto inhabitants to amass an archive that would eventually shine a light on the atrocities that occurred there. Aspler's testimony, recorded by McGill University in Montreal in 1995, is stored in USC Shoah Foundation's Visual History Archive.