J. Sarmiento, S. Trausan-Matu, and G. Stahl. presented at the International Symposium on Organizational Learning and Knowledge Work Management (OL-KWM 2005), page 88-99. Bucharest, Romania, (2005)
M. Sasman, A. Olivier, and L. Linchevski. Fifth Annual Congress of the Association for Mathematics Education of South Africa, 1, page 177-182. Port Elizabeth, Port Elizabeth Technikon, (1999)
M. Scaife, Y. Rogers, F. Aldrich, and M. Davies. CHI '97: Proceedings of the SIGCHI conference on Human factors in computing systems, page 343-350. New York, NY, USA, ACM Press, (1997)