@bookTönnies_1997, place=Trier, title=Samuel Beckett’s Dramatic Strategy. Audience Laughter and the Postmodernist Debate, publisher=WVT, author=Tönnies, Merle, year=1997 
LibreCat: /record/6752

@articleTönnies_1996, title=The Spectator as Participant: The Role of Integrating Audience Laughter in Samuel Beckett’s Drama, volume=11, number=2, journal=Forum Modernes Theater, author=Tönnies, Merle, year=1996, pages=185–196 
LibreCat: /record/9626