6[3]The Art and Craft of Harvard Case Teaching Method, "Because Wisdom Can't be Told", Harvard Alumni Bulletin, October 19,1940
7[4]Teaching and the Case Method, Louis B. Barnes, C. Roland Christensen, and Abby J. Hansen, Harveard Business School Press, 1994.
8[5]Teaching with eases, James A. Erskine, Michiel R. Leenders, Louise A. Mauffette- Leenders, Richard Ivey School of Business, Senton Printing,London, Ontario, Canada, 1998.