Development of Thick Wall Welding and Cutting Tools for ITER. - Masataka Nakahira; Hiroyuki Takahashi; Kentaro Akou; Koichi Koizumi (J. Robotics Mechatronics, 1998)

Necessary and Sufficient Numbers of Cards for the Transformation Protocol. - Koichi Koizumi; Takaaki Mizuki; Takao Nishizeki (COCOON, 2004)

A Revised Transformation Protocol for Unconditionally Secure Secret Key Exchange. - Koichi Koizumi; Takaaki Mizuki; Takao Nishizeki (Theory Comput. Syst., 2008)