Nikolaou, Aggeliki, and Costas Tsolakidis. “Three Dimensional Virtual Environments As a Tool for Development of Personal Learning Networks”. International Journal of Emerging Technologies in Learning (iJET) 8, no. S1 (January 28, 2013): pp. 79–88. Accessed April 18, 2024. https://online-journals.org/index.php/i-jet/article/view/2365.