SpaceTag: An Overlaid Virtual System and Its Applications. - Hiroyuki Tarumi; Ken Morishita; Megumi Nakao; Yahiko Kambayashi (ICMCS, Vol. 1, 1999)

Communication through virtual active objects overlaid onto the real world. - Hiroyuki Tarumi; Ken Morishita; Yusuke Ito; Yahiko Kambayashi (CVE, 2000)

Public Applications of SpaceTag and Their Impacts. - Hiroyuki Tarumi; Ken Morishita; Yahiko Kambayashi (Digital Cities, 2000)