HAL II: a mixed level hardware logic simulation system. - Shigeru Takasaki; Tohru Sasaki; Nobuyoshi Nomizu; Hiroshi Ishikura; Nobuhiko Koike (DAC, 1986)

HAL III: function level hardware logic simulation. - Shigeru Takasaki; Nobuyoshi Nomizu; Yoshihiro Hirabayashi; Hiroshi Ishikura; Masahiro Kurashita; Nobuhiko Koike; Toshiyuki Nakata 001 (ICCD, 1990)