<p> REFERENCES</p><p>M. Y. Li, T. F. Liao, and c. Y. Lai, “ A social recommender mechanism for improving knowledge sharing in online forums,” Information Processing & Management. 2012. C. M. Chiu, M. H. Hsu, and E. T. Wang, “Understanding knowledge sharing in virtual communities: An integration of social capital and social cognitive theories,” Decision support systems, 42(3), 1872-1888. 2006. C. M. Ridings and D. Gefen, “Virtual Community Attraction: Why People Hang Out Online,” Journal of Computer-Mediated Communication, 2004. Sudanese-Online Discussion Forum : http://www.sudaneseonline.com. C. M. Ridings, M. Catherine, David Gefen, and Bay Arinze, "Some antecedents and effects of trust in virtual communities," The Journal of Strategic Information Systems 11.3 (2002): 271-295. H. Rheingold, "Virtual communities-exchanging ideas through computer bulletin boards," Journal of Virtual Worlds Research 1.1 (2008). B. van den Hooff, A. P.Schouten and S. Simonovski, “What one feels and what one knows: the influence of emotions on attitudes and intentions towards knowledge sharing,” Journal of Knowledge Management, 16(1), 148-158. C. L. Hsu, and J. C. C. Lin, “Acceptance of blog usage: The roles of technology acceptance, social influence and knowledge sharing motivation,” Information & Management, 45(1), 65-74, 2008. H. W. Kim, J. R. Zheng, and S. Gupta, “Examining knowledge contribution from the perspective of an online identity in blogging communities," Computers in Human Behavior, 27(5), 1760-1770.2011. M. M. Wasko and s. Faraj, “Why should I share? Examining social capital and knowledge contribution in electronic networks of practice,” Mis Quarterly, 35-57.2005. T. Zhou, “Understanding online community user participation: a social influence perspective,” Internet Research, 21(1), 67-81. 2011. Hossain, Liaquat, and Anjali de Silv. "Exploring user acceptance of technology using social networks." The Journal of High Technology Management Research 20, no. 1, 2009: 1-18. F. D. Davis, “Perceived usefulness, perceived ease of use, and user acceptance of information technology,” MIS Quarterly, 13(3), 319–340, 1989. C.H. Chun, and Yang, “The intellectual development of the technology acceptance model: A co-citation analysis,” International Journal of Information Management, 31, pp. 128–136. 2011. Mathieson, Kieran. "Predicting user intentions: comparing the technology acceptance model with the theory of planned behavior." Information systems research 2.3 (1991): 173-191. Venkatesh, Viswanath, and Fred D. Davis. "A theoretical extension of the technology acceptance model: four longitudinal field studies," Management science 46.2 , pp.186-204. 2000. C. L. Hsu and H. P. Lu, “Why do people play on-line games? An extended TAM with social influences and flow experience,” Information & Management, 41(7), 853-868. 2004. </p>