@article{AchaEtAlAICOM10,
 author = "Roberto As{\'\i}n Ach{\'a}, Robert Nieuwenhuis, Albert Oliveras, Enric Rodr{\'\i}guez-Carbonell",
 title = "Practical algorithms for unsatisfiability proof and core generation in SAT solvers",
 journal = "AI Communications",
 volume = 23,
 number = 2-3,
 year = 2010,
 pages = "145--157 ",
}