[1] M. J. Weber. Selective excitation and decay of Er3+ Fluorescence in LaF3. Phys. Rev., 1967, 156(2): 231～241

[2] A. A. Kaminskii. Laser Crystal, Springer-Verlag, Berlin, Heideberg, New York, 1981

[3] P. W. France. A review of Fluoride glass fibre lasers. Extended Abstracts 6th Int. Symp. Halide Glasses., 1989, 51～54

[4] P. LeGall, J. L. Adam, J. Lucas. Optical properties of Nd3+ and transition metalions in InF3-based fluoride glasses. Mat. Sci. Forum., 1991, 67(2): 509～514

[5] B. R. Judd. Optical absorption intensities of rare-earth ions. Phys. Rev., 1962, 127(3): 750～761

[6] G. S. Ofelt. Intensities of crystal spectra of rare-earth ions. J. Chem. Phys., 1962, 37(3): 511～520

[7] W. T. Carnall, P. R. Fields, K. Rajnak. Electronic enery levels in the trivalent Lanthanide Aquo ions. J. Chem. Phys., 1968, 49(10): 4424～4442

[8] M. J. Weber. Probabilities for radiative and nonradiative decay of Er3+ in LaF3. Phys. Rev., 1967, 157(2): 262～272