9Li Taisien, Tan Yongji, Peng Yuejun, et al. Mathematical methods for the SP well-logging[M]. Boston: Kluwer Academic Publishers, 1991:343 - 349.
10Li Taisien, Tan Yongji, Peng Yuejun. Mathematical model and method for spontaneous potential well- logging[J]. European Journal of Applied Mathematics, 1994,5 : 123 - 139.