1. Les problèmes de coloration en théorie des graphes;Berge;Publ. Inst. Stat. Univ. Paris,1960
2. On rigid circuit graphs;Dirac;Abh. Math. Sem. Univ. Hamburg,1961
3. Algorithmic Graph Theory and Perfect Graphs;Golumbic,1980
4. Polynomial algorithms for perfect graphs;Grötschel,1984
5. H. Aït Haddadène, S. Gravier, On weakly diamond-free Berge graphs, Discrete Math., submitted.