Knowles, Alan. “Online Education Using Learning Objects R. McGreal (Ed.) London: RoutledgeFalmer, 2004, 361 Pages”. International Journal of E-Learning & Distance Education Revue Internationale Du E-Learning Et La Formation à Distance, vol. 20, no. 1, Dec. 2007, pp. 104-6, https://www.ijede.ca/index.php/jde/article/view/79.