S. Hanatani, H. Nakamura, S. Tanaka, C. Notsu, H. Sano, and K. Ishida, "Superlattice avalanche photodiode with a gain-bandwidth product larger than 100 GHz for very-high-speed systems,"
in Conference on Optical Fiber Communication/International Conference on Integrated Optics and Optical Fiber Communication,
Vol. 4 of 1993 OSA Technical Digest Series
(Optical Society of America, 1993), paper ThG3.