IEEE COMMUNICATIONS LETTERS, vol. 9, no. 2, page. 112 - 114, 2005-02
IEICE TRANSACTIONS ON COMMUNICATIONS, vol. E88B, no. 6, page. 2676 - 2680, 2005-06
PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS, vol. 19, no. 4, page. 364 - 387, 2010-08