[2] K. G. Herngyist, Α. Η. Firester; Rev. Sci. Iustrum., 1975, 46, 1040.
[3] H. Kogelnik; Proceedings of the Symposium on Quant-Optics (Polytechnic Press, 1964), 333
[4] D. Herriott, H. Kcgelnik, R. Kcmpfner; Appl. Opt., 1964, 3, 523.
[5] A. G. Fox, T. Li; Bell. Sys. Tech. J., 1961, 40, No. 2, 453~488