7Peter Collier.??The Impact on Topographic Mapping of Developments in Land and Air Survey: 1900-1939(J)Cartography and Geographic Information Science . 2002 (3)
8Wu C.VisualSFM:A visual structure from motion system. http://homes.cs.washington.edu/-ccwu/vsfm . 2011
9Colin A Ronan.The Shorter Science and Civilisation in China:An Abridgement of Joseph Needham’’s Original Text. . 1981
10Japan National Institute of Informatics.Complete Map of Peking,Qianlong period. http://dsr.nii.ac.jp/toyobunko/II-11-D-802/map/ . 2015