Roberto Javier López-Sastre J. Renes-Olalla Pedro Gil-Jiménez Saturnino Maldonado-Bascón Visual Word Aggregation. 676-683 2011 IbPRIA http://dx.doi.org/10.1007/978-3-642-21257-4_84 conf/ibpria/2011 db/conf/ibpria/ibpria2011.html#Lopez-SastreRGM11