@Conference{liu12super, title = {{A Markov semi-supervised clustering approach and its application in topological map extraction}}, author = {Ming Liu and Francis Colas and Fran\c{c}ois Pomerleau and Roland Siegwart}, booktitle = {2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2012.(IROS 2012)}, year = {2012} }