Radim Belohlávek Bernard De Baets Jan Outrata Vilém Vychodil Trees in Concept Lattices. 174-184 2007 conf/mdai/2007 MDAI http://dx.doi.org/10.1007/978-3-540-73729-2_17 db/conf/mdai/mdai2007.html#BelohlavekBOV07a