Parvathi Chundi Daniel J. Rosenkrantz Information Preserving Time Decompositions of Time Stamped Documents<sup>*</sup>. 41-65 2006 13 Data Min. Knowl. Discov. 1 http://dx.doi.org/10.1007/s10618-005-0035-1 db/journals/datamine/datamine13.html#ChundiR06