Sandra Mitchell Hedetniemi Stephen T. Hedetniemi Alice A. McRae Dee Parks Jan Arne Telle Iterated colorings of graphs. 81-108 2004 278 Discrete Mathematics 1-3 http://dx.doi.org/10.1016/S0012-365X(03)00247-4 db/journals/dm/dm278.html#HedetniemiHMPT04