representation of road environment understanding for a mobile robot by picture interpretation language PILS. - Hideo Mori; Izumi Fudaba; Hiroaki Yokoyama (Syst. Comput. Jpn., 1986)

Representations of Locally Inverse *-Semigroups. - Teruo Imaoka; Isamu Inata; Hiroaki Yokoyama (Int. J. Algebra Comput., 1996)