@article{DBLP:journals/fuin/KonczakSL03, title = {Graphs and Colorings for Answer Set Programming with Preferences}, author = {Konczak, Kathrin and Schaub, Torsten and Linke, Thomas}, journal = {Fundam. Inform.}, number = {2-4}, pages = {393--421}, volume = {57}, year = {2003} }