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8Barbara J Duch, Susan E Groh, and Deborah E Allen. The power of problem - based learning: a practical "how to" for teaching undergraduate courses in any discipline. Sterling. Va. : Stylus Pub., 2001.6.7 40-44. 9.
9Peter Schwartz, Stewart Mennin and Graham Webb. Problem - based learning: case studies, experience and practice. London: Kogan Page, 2001, p 2.
