Martin Brown Nicholas Costen Shigeru Akamatsu Efficient Calculation of the Complete Optimal Classification Set. 307-310 2004 conf/icpr/2004 ICPR (2) https://doi.org/10.1109/ICPR.2004.1334183 https://doi.ieeecomputersociety.org/10.1109/ICPR.2004.1334183 db/conf/icpr/icpr2004-2.html#BrownCA04