On Dual Based Lower Bounds for the Sequential Ordering Problem with Precedences and Due Dates Egileak: A. Alonso-Ayuso, P. Detti, L.F. Escudero y M.T. Ortuño Urtea: 2003 Aldizkaria: Annals of Operations Research Informazio gehigarria http://link.springer.com/article/10.1023%2FB%3AANOR.0000004765.69773.41
