[1] Morris R С, Cline С F. USP 3997853 14 Dec., 1976

[2] Walling J et al. IEEE J. Quant. Electr., 1980; QE-16(12): 1302

[3] Struve B, Huber G. Appl. J. Phys., 1983; B30: 117

[4] Pruss D, Huber G, Beimowski A et al. Appl. Phys., (В) 1982; 28(7): 355

[5] Kaminski A A, Badasarov Kh S, Bagomolova G Α et al. Phys. Status Solidi (a), 1976,34(2): К109

[6] Zhang Lehui, Liu Hairun, Lin Chengtian. J. of Synthetic Crystals，1985; 14(3/4): 23

[7] Hecht Jeff. Lasers and Applications，1984; (9): 77

[8] Ma Xiaoshan. J. of Synthetic Crystrls, 1985; 14 (1) : 38

[9] Xiaoshan, Hou Yinchun. Reported in Rational Conference on Gem and Minerals, 25 May (1982)

[10] Shand Μ L, Walling J C. IEEE J. Quant. Electr.9 1982; QE-18: 1829

[11] Buchert J, Katz A, Alfanno Ε R. IEEE J. Quant. Electr , 1983; QE-19: 19

[12] Kolbe W, Petermann K, Hnber G. W1I P. 100 CLEO,84

[13] Galakhov F Ya. Izvest. Alcad. Nauk SSSB, Otdel Khim. Nauk, 1957; 1035

[14] Ma Xiaoshan, Hou Yinchun, Wang Siting et al. Acta Silicata, 1984; 21 (2):131