1. Annett, N. (1997 Oct 5). Collaborative learning: definitions, benefits, applications and dangers in the writing center. University of Richmond, Virginia; USA. Retrieved 5 Nov.2011, from: writing2.richmond.edu/training/fall97/nanne/collaboration.html.
2. Astin, A.W. (1977). Four critical years: Effects of college beliefs, attitudes and knowledge. San Francisco, USA. Jossey Bass Publishing.
3. Austin, J.E. (2000). Principles for Partnership. Journal of Leader to Leader. 18 (Fall), pp. 44-50.
4. Bean, J. (1996). Engaging ideas, the professor's guide to integrating writing, critical thinking, and active learning in the classroom, San Francisco; USA. Jossey Bass Publishing.
5. Bonoma, J., Tedeschi, J., Helm, B. (1974). Some effects of target cooperation and reciprocated promises on conflict resolution. Journal of Sociometry. 37(2), pp. 251-261.