1. AN Chang-qiang, SONG Zhong-he, CHEN Guo-ying,et al. 1993. 3-D shear velocity structure in north-west China [J].Acta Geophysica Sinica,36(3): 317–325 (in Chinese).
2. CHEN Guo-ying, SONG Zhong-he, AN Chang-qiang,et al. 1991. Three dimensional crust and upper mantle structure of the North China region [J].Acta Geophysica Sinica,34(2): 172–181 (in Chinese).
3. Ditmar P G, Yanovskaya T B. 1987. An extension of the Backus-Gilbert technique for estimating lateral variations of surface wave velocities [J].Izv Akad Nauk SSSR, Fiz Zemli, (6): 30–60 (in Russian).
4. Dziewonski A, Bloch S, Landisman M. 1969. A technique for the analysis of transient seismic signals [J].Bull Seism Soc Amer,59: 427–444.
5. FENG Rui, ZHU Jie-shou, DING Yun-yu,et al. 1981. Crustal structure in China from surface wave [J].Acta Seismologica Sinica,3(4): 335–349 (in Chinese).