@techreport{
    Niemela93:thesis,
    author = {Niemel{\"a}, Ilkka},
    title = "Autoepistemic Logic as a Unified Basis for Nonmonotonic Reasoning",
    address = "Espoo, Finland",
    number = "A24",
    month = "August",
    flags = "copy",
    year = "1993",
    type = "Doctoral dissertation. Research report",
    institution = "Helsinki University of Technology, Digital Systems Laboratory"
}