jgg     2013 33 (2):  151-154    ISSN: 0412-1961  CN: 21-1139/TG DISTRIBUTION OF GPS SLANT DELAY FOR WATER VAPOR TOMOGRAPHY IN YANGTZE RIVER DELTA 1)Earthquake Administration of Jiangsu Province, Nanjing 210014 2)Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030 3)College of Surveying and Geo-informatics, Tongji University, Shanghai 200092 Received: 2012-08-20  Revised: null  Online: 2013-04-18 Supporting info