@phdthesis{
    HUT-TCS-A58,
    author = "Simons, Patrik",
    institution = "Helsinki University of Technology, Department of Computer Science and Engineering, Laboratory for Theoretical Computer Science",
    title = "Extending and Implementing the Stable Model Semantics",
    year = "2000",
    number = "A58",
    month = "April",
    note = "Doctoral dissertation",
    address = "Espoo, Finland",
    owner = "MM",
    type = "Research Report",
    pages = "91"
}