@inproceedings{Garrell_iros2009, author = {A. Garrell and A. Sanfeliu and F. Moreno-Noguer}, title = {Discrete Time Motion Model for Guiding People in Urban Areas using Multiple Robots}, booktitle = {Proceedings of the International Conference on Intelligent Robots and Systems (IROS)}, pages = {486-491}, year = {2009} }