D. Payton, M. Daily, B. Hoff, M. Howard, and C. Lee. Mobile Robots / Telemanipulator and Telepresence Technologies, volume 4195 of SPIE Proceedings, page 67-75. SPIE, (2000)
M. Hoff. Pontifical Catholic University of Campinas, Brazil, (2001)ndltd.org (oai:agregador.ibict.br.BDTD_PUC_CAMPINAS:oai:tede.bibliotecadigital.puc-campinas.edu.br:tede/407).