%visual method used (not only) for charging station localization
@inproceedings{krajnik_external,
        author = {Krajn{\' i}k, T. and Nitsche, M. and Faigl, J. and Duckett, T. and Mejail, M. and P{\v r}eu{\v c}il, L.},
        title = {{External Localization System for Mobile Robotics}},
        booktitle = {{Proceedings of the International Conference on Advanced Robotics}},
        publisher = {IEEE},
        address = {Montevideo},
        year = {2013},
        language = {English}
}