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The principle of the positioning system based on communication satellites GuoXiang AI, HuLi SHI, HaiTao WU, ZhiGang LI & Ji GUO（Sci China Ser G-Phys Mech Astron Mar. 2009 vol. 52  no. 3  472-488） 

Barometric altimetry system as virtual constellation applied in CAPS GuoXiang AI, PeiXuan SHENG, JinLin DU, YongGuang ZHENG, XianDe CAI, HaiTao WU, YongHui HU, Yu HUA & XiaoHui LI（Sci China Ser G-Phys Mech Astron  Mar. 2009  vol. 52  no. 3  376-383）