3Molenaar, M, An Introduction to the theory of spatial objects modelling[M]. Taylor&Francis, London, 1998.
4Raper, J.F, T. McCarthy and D. Unwin,Multi dimensional Virtual Reality Geographic Information System (VRGIS): research guidelines [A]. in: Proceedings GISRUK 98[C]. Edinburg, UK, 1998,6.
5Tempfli, K. and M. Pilouk, Practical photogrammetry for 3D-GIS[A]. in: Proceedings of ISPRS, Vol. ⅩⅩⅪ, Part B4 [C].Vienna, Austria, 1996,pp. 859-867.
6Wang, Z, Digital Photogrammetric Data acquisition for 3D GIS [D]. MSc thesis,ITC, The Netherlands, 1994.