@article{
    SNS2002:aij,
    author = {Simons, Patrik and Niemel{\"a}, Ilkka and Soininen, Timo},
    note = "",
    title = "Extending and Implementing the Stable Model Semantics",
    journal = "Artificial Intelligence",
    number = "1--2",
    month = "",
    volume = "138",
    flags = "SA-53695",
    year = "2002",
    pages = "181--234"
}