Xin Chen Xiaohua Hu Xiajiong Shen Spatial Weighting for Bag-of-Visual-Words and Its Application in Content-Based Image Retrieval. 867-874 2009 PAKDD http://dx.doi.org/10.1007/978-3-642-01307-2_90 conf/pakdd/2009 db/conf/pakdd/pakdd2009.html#ChenHS09