Sánchez García, MiguelSobrón Fernández, María InésVitoriano Villanueva, Begoña2023-06-202023-06-201998M. Sánchez-García, M.I. Sobrón, B. Vitoriano: [No title found]. Annals of Operations Research. 81, 343-356 (1998). https://doi.org/10.1023/A:10189694104310254-533010.1023/A:1018969410431https://hdl.handle.net/20.500.14352/57923Balas and Ng [1,2] characterized the class of valid inequalities for the set covering polytope with coefficients equal to 0, 1 or 2, and gave necessary and sufficient conditions for such an inequality to be facet defining. We extend this study, characterizing the class of valid inequalities with coefficients equal to 0, 1, 2 or 3, and giving necessary and sufficient conditions for such an inequality to be not dominated, and to be facet defining.engjournal articlehttps//doi.org/10.1023/A:1018969410431http://download.springer.com/static/pdf/772/art%253A10.1023%252FA%253A1018969410431.pdf?auth66=1362498077_a20ac7d2d50f37e5cf4ba2af58951e31&ext=.pdfrestricted access519.8Polyhedral combinatoricsCombinatorial optimizationValid inequalitiesSet coveringFacetsInvestigación operativa (Matemáticas)1207 Investigación Operativa