1HUGENTOBLER, SCHAER S, FRIDEZ P. Bernese GPS Software Version 4.2 [ EB/OL]. [2009-03-10]. http:// mat. fe. ul. pt/eg/ge/DOCU42_1, pdf , 2001.
2HOFMANN-WELLENHOF B, LICHTENEGGER H, COLLINS J. Global Positioning System Theory and Practice [M]. Wien:Springer, 1992.
3COLLINS J P. Assessment and Development of a Tropospheric Delay Model for Aircraft Users of the Global Positioning System [ R ]. Canada: University of New Brunswick, 1999.