Rainer Kümmerle Patrick Pfaff Rudolph Triebel Wolfram Burgard Active Monte Carlo Localization in Outdoor Terrains Using Multi-level Surface Maps. 29-35 2007 AMS http://dx.doi.org/10.1007/978-3-540-74764-2_5 conf/ams/2007 db/conf/ams/ams2007.html#KummerlePTB07