Grzegorz Popek Radoslaw Katarzyniak Measuring Similarity of Observations Made by Artificial Cognitive Agents. 693-702 2008 KES-AMSTA http://dx.doi.org/10.1007/978-3-540-78582-8_70 conf/kesamsta/2008 db/conf/kesamsta/kesamsta2008.html#PopekK08