1. The Designs and Analysis of Computer Algorithms;Aho,1974
2. Application of the join-irreducible excess function to semi-modular lattices;Avann;Math. Ann.,1961
3. Remarques sur les propriétés métriques des ensembles ordonnés;Barthelemy;Math. Sci. Hum.,1978
4. Graphes et Hypergraphes;Berge,1970
5. Lattice Theory;Birkhoff,1967