Marcus Held Jan Puzicha Joachim M. Buhmann 452-458 http://papers.nips.cc/paper/1552-visualizing-group-structure http://nips.djvuzone.org/djvu/nips11/0452.djvu 1998 conf/nips/1998 NIPS db/conf/nips/nips1998.html#HeldPB98