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2. Representation; noyaux en theorie des graphes et hypergraphes;Duchet,1979
3. A note on kernel-critical graphs;Duchet;Discrete Math.,1981
4. A counterexample to a conjecture of Meyniel on KP-graphs;Galeana-Sánchez;Discrete Math.,1982
5. Seminúcleos de una digráfica;Neumann-Lara,1971