Atul Sajjanhar Guojun Lu Dengsheng Zhang Jingyu Hou Yi-Ping Phoebe Chen Spherical Harmonics and Distance Transform for Image Representation and Retrieval. 309-316 2009 IDEAL http://dx.doi.org/10.1007/978-3-642-04394-9_38 conf/ideal/2009 db/conf/ideal/ideal2009.html#SajjanharLZHC09