1[1]Al Gore.The digital earth-understanding our planet in the 21st century[R].1998.
2[2]Peter Berger et al.Towards a virtual reality interface for landscape visualization[EB/OL].http://www.ncgia.ucsb.edu/conf/SANTA-FE-CD-ROM/sf-papers/berger/paper.htm.1994.
3[3]Pajarola R B et al.OTAW'94-ViRGIS(Virtual Reality based Geographic Information Systems)[EB/OL].http://iamwww.unibe.ch/~www/WWW/CHOOSE/Articles/94-11/OTAW-94.Poster.5.html.1994.
4[4]Mather P M.An investigation into user requirements for advanced spatial decision support systems[EB/OL].http://www.geog.nottingham.ac.uk/~mather/vr.html.1996.
6[6]Reddy M,Leclerc Y G,Iverson L et al.Modeling the digital earth in VRML[R].AIC Technical Report No.559.SRI International,Menlo Park,CA,9 November,1998.
7[7]Theresa Marie Rhyne,Thomas Fowler.Examining dynamically linked geographic visualization[EB/OL].http://www.epa.gov/vislab/svc/publications/awma-gisvis.html.1996.
8[8]Robert M Edsall,Mark Harrower,Jeremy Mennis.Visualizing properties of temporal and spatial periodicity in geographic Data[EB/OL].http://www.geog.psu.edu/apoala/a-papers.htm.
9[9]Cignoni P,Puppo E,Scopigno R.Representation and visualization of terrain surfaces at variable resolution[J].The Visual Computer,1997,13(5):199~217.
10[10]Floriani L De,Puppo E.Hierarchical triangulation for multiresolution surface description[J].ACM Transactions on Graphics,1995,14(4):363~411.