International symposium Grenzen und Grenzüberschreitungen: Transnationale Filmbeziehungen der DEFA vor und nach dem Mauerbau (Borders and Border-crossings: DEFA’s Transnational Exchanges before and after the Erection of the Berlin Wall), organised by the Film Museum Potsdam, DEFA Film Library at Amherst and the Babelsberg Film and Television Academy, Potsdam, November 2011 (plenary speaker)