Jens Ketterer Jan Puzicha Marcus Held Martin Fischer Joachim M. Buhmann Dieter W. Fellner On Spatial Quantization of Color Images. 563-577 http://link.springer.de/link/service/series/0558/bibs/1406/14060563.htm 1998 conf/eccv/1998-1 ECCV (1) db/conf/eccv/eccv1998-1.html#KettererPHFBF98