2.2.2 spase://SMWG/Person/Wu.Baoyuan 2012-04-20T12:34:56.789 Wu Baoyuan Chinese Academy of Sciences, Institute of Geophysics, Beijing, China

Beijin Ming Tombs Geomagnetic Observatory, De Sheng Kou, Ming Tombs Town, Chang Ping County, Beijing 102213, China

wuby@mail.igcas.ac.cn