International Conference on Robotics and Automation, page. 1478 - 1483, 2000-04-24
International Conference Intelligent Robots and System, page. 913 - 918, 2001-10-29
International Conference Intelligent Robots and System, page. 1645 - 1650, 2002-10-01
International Conference Intelligent Robots and System, page. 2122 - 2127, 2002-10-01