J. Zhu, J. Hong, and J. Hughes. HYPERTEXT '01: Proceedings of the twelfth ACM conference on Hypertext and Hypermedia, page 131--132. New York, NY, USA, ACM, (2001)
J. Zhu, J. Hong, and J. Hughes. HYPERTEXT '01: Proceedings of the twelfth ACM conference on Hypertext and Hypermedia, page 131--132. New York, NY, USA, ACM, (2001)