'A'
K. S. Chiang and Q. Liu, "Long-period grating devices for application in optical communication," Proc. of the 5th International Con. on Optical Communications and Networs & the 2nd International Symp. on Advances and Trends in Fiber Optics and Applications, Chendu, China, Sep. 2006, pp. 128-133.
Authors' address:
Optoelectronics Research Centre and Dept. of Electronic Engineering, City Univ. of Hong Kong, Hong Kong, China

'B'
S. Kim, Y. Jeong, S. Kim, J. Kwon, N. Park, and B. Lee, "Control of the characteristics of a long-period grating by cladding etching," Applied Optics, vol. 39, no. 13, pp. 2038-2042, 2000.