1. Allen, E., Seaman, J.: Online Nation Five Years of Growth in Online Learning, vol. 1 (2007)
2. Barbeau, M.: WiMax/802.16 Threat Analysis, pp. 8–15 (2005)
3. Boella, G., van der Torre, L.: Security Policies for Sharing Knowledge in Virtual Communities. IEEE Transactions on Systems, Man, and Cybernetics Part A: Systems and Humans 36, 439–450 (2006)
4. Bruns, R., Dunkel, J., von Helden, J.: Secure Smart Card-Based Access to an e-Learning Portal. In: Proceedings of the 5th International Conference on Enterprise Information Systems (ICEIS), Angers, France (2003)
5. Conole, G., Smith, J., White, S.: A critique of the impact of policy and funding. In: Conole, G., Oliver, M. (eds.) Contemporary Perspectives in E-Learning Reserach Themes, Methods and Impact on Practice, pp. 38–54. Routledge, London (2007)