JOURNAL OF APPLIED PHYSICS, vol. 69, no. 9, page. 6699 - 6700, 1991-05-01
, 1996-01
JOURNAL OF ROBOTIC SYSTEMS, vol. 11, no. 2, page. 117 - 128, 1994-01
ROBOTICA, vol. 10, page. 255 - 262, 1992-05
, 1997-01
JOURNAL OF ROBOTIC SYSTEMS, vol. 10, no. 6, page. 811 - 833, 1993-09