@inproceedings {tipaldi11iros,
	author = {Tipaldi, Gian Diego and Arras, Kai O.},
	title = {{Please do not disturb! Minimum interference coverage for social robots}},
	booktitle = {Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)},
	year = {2011},
	pages = {1968{\textendash}1973},
	address = {San Francisco, USA},
	url = {http://www.informatik.uni-freiburg.de/~tipaldi/papers/tipaldi11iros.pdf}
}