1. ZHAO Xue-feng, TIAN Shi-zhu, and ZHOU Zhi,Journal of Optoelectronics·Laser,14 (2003), 171, (in Chinese)
2. XUE Lin, ZHAO Hua-feng, and SUN Jun.Chinese journal of Lasers,A28 (2001), 999. (in Chinese)
3. LING Long-bin, ZHANG Wei-gang, and ZHANG Qi-da,Journal of Optoelectronics · Laser,12 (2001), 1152 (in Chinese).
4. LIAO Yan-biao, Optical Fiber Optics Beijing Science Publishing house, Beijing, 2000.
5. S. C. Rashleigh and R. Ulrich,Opt. Lett,5 (1980), 35.