8K. Curran, "An online collaboration environment," [J]. Education and information technologies, vol. 7. no. 2, pp. 41-53, November 2004.
9Bhargava, P. Antonakakis, J. Cunningham, C. Zehnder, A. T, "Web-based virtual torsion laboratory," [J].Computer application in engineering education, vol. 14. no. 1, pp. 1-8, January 2006.