Christian Plagemann Felix Endres Juergen Michael Hess Cyrill Stachniss Wolfram Burgard Monocular range sensing: A non-parametric learning approach. 929-934 2008 ICRA http://dx.doi.org/10.1109/ROBOT.2008.4543324 conf/icra/2008 db/conf/icra/icra2008.html#PlagemannEHSB08