sentences:  He was the author of books, among others, on Anna Seghers, Christa Wolf, Max Frisch, and Peter Weiss.Stephan was also the first researcher who obtained access to the documents which the FBI kept on German exile writers such as Bertolt Brecht, Lion Feuchtwanger, Thomas Mann and Anna Seghers.At the OSU Mershon Center, Stephan concentrated on international security and US-European cultural relations.