6Csikszentmihalyi, Mihaly, Judith Lefevre. "Optimal Experience in Work and Leisure", Journal of Personality and Social Psychology, 1989, 56(5): pp815-822.
7The McKITTRICK HOTEL:EMURSIVE PRESENTS PUNCHDRUNK's Sleep No More.
8Hilton Als, The Theatre, "Shadow and Act", The New Yorker, May.2, 2011 ,pp86.