jgg     2008 28 (2):  77-80    ISSN: 0412-1961  CN: 21-1139/TG COMPARISON OF INTERPOLATING AND FITTING IGS PRECISE EPHEMERIS Li Mingfeng; Jiang Guoyan ;and Zhang Kai College of Civil Engineering, Nanjing University of Technology, Nanjing 210009 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null