The BBC's Michael Rossi reports on the discovery of wax cylinders from Moisei Beregovsky's original expeditions in the 1940s to collect songs from Holocaust survivors in Ukraine. Here, he interviews Mila Sholokhova who discovered Beregovsky's collection in Ukraine, along with University of Toronto professor Anna Shternshis and Holocaust survivor Grigori Shmulevich - whose mother was recorded on these cylinders