IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, vol. 17, no. 6, page. 857 - 869, 2001-12
IEEE TRANSACTIONS ON AUTOMATIC CONTROL, vol. 46, no. 10, page. 1618 - 1623, 2001-10
MECHATRONICS, vol. 11, no. 3, page. 325 - 343, 2001-04
ADVANCED ROBOTICS, vol. 15, no. 5, page. 575 - 588, 2001-01