@INPROCEEDINGS{Schroeter-ECMR-2007,
  author = {Schroeter, {\relax Ch}ristof and Boehme, Hans-Joachim and Gross,
    Horst-Michael},
  title = {Memory-Efficient Gridmaps in {Rao}-{Blackwellized} Particle Filters
    for {SLAM} Using Sonar Range Sensors},
  booktitle = {Europ. Conf. on Mobile Robots (ECMR)},
  year = {2007},
  pages = {138--143},
  publisher = {Albert-Ludwigs-Universitaet Freiburg -- Universitaetsverlag}
}