4COUCLELIS H.The Death of Distance [J].Environment and Planning B: Planning and Design,1996,23: 387-389.
5DODGE M.Cybergeography[J].Environment and Planning B: Planning and Design,2001,28:1-2.
6GONG Jian-hua,LIN Hui.Virtual Geographic Environments-A Geographic Perspective on Online Virtual Reality [M].Beijing: High Education Press,2001.(in Chinese)
7LIN Hui,GONG Jian-hua.Exploring Virtual Geographic Environments [J].Geographic Information Sciences,2001,7(1):1-7.
8GONG Jian-hua,LIN Hui.Virtual Geographic Environments and Virtual Geography[A].Proceedings 9th International Symposium on Spatial Data Handling[C].Beijing:[s.n.] 2000.28-39.
9GONG Jian-hua,LIN Hui.Virtual Geographic Environments: Concept,Design,and Applications[A].Proceedings of the International Symposium on Digital Earth(ISDE)[C].Beijing: Science Press,1999.369-375.
10ACTIVE WORLDS.Active Worlds - the Home of the 3D Internet[EB/OL].http://www.activeworlds.com/,2001-12-01/2001-12-25.