1. V. S. Kondratenko, RF Patent No. 2024441.
2. S. V. Shalupaev, E. B. Shershnev, A. N. Serdyukov, et al., Ceramics. Polish Ceramic Bulletin 65, 75 (2001).
3. V. K. Sysoev, B. P. Papchenko, A. V. Zakharchenko, et al., Opt. Zh. 71(2), 65 (2004).
4. C. Tsai and H. Chen, J. Mater. Proc. Technol. 136, 166 (2003).
5. S. V. Shalupaev, E. B. Shershnev, Yu. V. Nikityuk, et al., Opt. Zh. 73(5), 62 (2005).