T. Nakamura et al., "Self aligned Transistor with sidewall base contact" IEEE Jl. of Solid-state Circuits, SC-17, pp.226-230, April 1982
H. Nakashiba et al., " An advanced PSA technology for high speed Bipolar LSI," IEEE Jl. of Solid-state Circuits, SC-15, pp. 455-459, Aug 1980.
D. J. Roulston and A. Kapoor, "Polysilicon Emitter Transistors" IEEE Press Book, 1989.