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