Ingo Schmitt Nadine Schulz Gunter Saake Multi-level Weighting in Multimedia Retrieval Systems. 353-364 2002 conf/edbtw/2002 EDBT Workshops http://dx.doi.org/10.1007/3-540-36128-6_20 db/conf/edbtw/edbtw2002.html#SchmittSS02