WASET
    Melvin Ballera and  Mosbah Mohamed Elssaedi and  Ahmed Khalil Zohdy,  Collaborative E-Learning with Multiple Imaginary Co-Learner: Design, Issues and Implementation.   journal   = {International Journal of Educational and Pedagogical Sciences}, [online]. World Academy of Science, Engineering and Technology.
    January 2013, vol. 73(1). 72 - 76
    [viewed 04 May 2024]. Available from: https://publications.waset.org/pdf/8059.