Graf, Birgit; Hans, Matthias; Schraft, Rolf D. (2004). "Care-O-bot II—Development of a Next Generation Robotic Home Assistant". Autonomous Robots. 16 (2): 193–205. doi:10.1023/B:AURO.0000016865.35796.e9. S2CID6423156.
Graf, Birgit; Hans, Matthias; Schraft, Rolf D. (2004). "Care-O-bot II—Development of a Next Generation Robotic Home Assistant". Autonomous Robots. 16 (2): 193–205. doi:10.1023/B:AURO.0000016865.35796.e9. S2CID6423156.