Asanobu Kitamoto Mikio Takagi The area proportion distribution - relationship with the internal structure of mixels and its application to image classification. 57-76 2000 31 Systems and Computers in Japan 5 http://dx.doi.org/10.1002/(SICI)1520-684X(200005)31:5<57::AID-SCJ6>3.0.CO;2-1 db/journals/scjapan/scjapan31.html#KitamotoT00