%0 Journal Article %A Polák, Jaroslav %T Aggregation and disaggregation in Markov chains %J Commentationes Mathematicae Universitatis Carolinae %D 1990 %P 403-404 %V 31 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMUC_1990__31_2_a24/ %G en %F CMUC_1990__31_2_a24