M. Nielsen, J. D. Buron, and B. Dagens, "Demonstration of an all-optical 3-input xor-gate and a data encryption/decryption scheme at 10 Gb/s based on all-active Mach-Zehnder interferometers,"
in Optical Amplifiers and Their Applications, J. Nagel, S. Namiki, and L. Spiekman, eds.,
Vol. 77 of OSA Trends in Optics and Photonics Series
(Optical Society of America, 2002), paper OTuD3.