1. Perfect graphs and kernels;Berge;Bull. Inst. of Math. Acad. Sinica,1988
2. Graphes noyau-parfaits;Duchet;Ann. Discrete Math.,1980
3. On kernels and semi-kernels of digraphs;Galeana-Sanchez;Discrete Math.,1984
4. On directed graphs with an independent covering set;Milner,1988
5. The Theory of Games and Economic Behavior;von Neumann,1953