1. Digraphs. Theory, Algorithms and Applications;Bang-Jensen,2002
2. Expressive power of digraph solvability;Bezem;Ann. Pure Appl. Log.,2012
3. Graph Theory;Bondy,2008
4. Perfect graphs, kernels and cores of cooperative games;Boros;Discrete Math.,2006
5. On the Computational Complexity of Finding a Kernel;Chvátal,1973