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[3] L. R. Wilcox, W. E. Lamb Jr.. Rate equations versus Bloche quations in multiphoton ionization. Phys. Rev., 1960, 119(6): 1915～1933

[4] J. R. Ackerhalt, B. W. Shore. Rate equation versus Bloche quations in multiphoton ionization. Phys. Rev. (A), 1977, 16(1): 277～282

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[6] J. E. Bjorkholm, P. F. Liao. Resonant enhancement of two-photon absorption in sodium vapor. Phys. Rev. Lett., 1974, 33(3): 128～131