Kathie Cameron Elaine M. Eschen Chính T. Hoàng R. Sritharan The Complexity of the List Partition Problem for Graphs. 900-929 2007 21 SIAM J. Discrete Math. 4 http://dx.doi.org/10.1137/060666238 db/journals/siamdm/siamdm21.html#CameronEHS07