@InProceedings{Loyer04a, author = "Loyer, Yann and Straccia, Umberto", title = "The Approximate Well-founded Semantics for Logic Programs with Uncertainty", booktitle = 29th International Symposium on Mathematical Foundations of Computer Science (MFCS-2004), publisher = "Springer Verlag", series = "Lecture Notes in Computer Science", number = "3153", pages = "513-524", address ="Bratislava, Slovak Republic", year ="2004" }