David S. Johnson Shankar Krishnan Jatin Chhugani Subodh Kumar Suresh Venkatasubramanian Compressing Large Boolean Matrices using Reordering Techniques. 2004 conf/vldb/2004 13-23 VLDB db/conf/vldb/vldb2004.html#JohnsonKCKV04 http://www.vldb.org/conf/2004/RS1P1.PDF