A study on the scattering of radio waves from buried spherical targets using the step frequency radar. - Alois P. Freundorfer; Keigo Iizuka (IEEE Trans. Geosci. Remote. Sens., 1993)

Axi-vision Camera: A Three-dimensional Camera. - Masahiro Kawakita; Keigo Iizuka; Tahito Aida; Hiroshi Kikuchi; Hideo Fujikake; Jun Yonai; Kuniharo Takizawa (Three-Dimensional Image Capture and Applications, 2000)

Real-time three-dimensional video image composition by depth information. - Masahiro Kawakita; Keigo Iizuka; Tahito Aida; Taiichirou Kurita; Hiroshi Kikuchi (IEICE Electron. Express, 2004)

Real-time depth-mapping three-dimension TV camera (Axi-Vision camera). - Masahiro Kawakita; Keigo Iizuka; Yoshiki Iino; Hiroshi Kikuchi; Hideo Fujikake; Tahito Aida (Syst. Comput. Jpn., 2006)