@PHDTHESIS\{IMM2007-05223,
    author       = "J. V. Christensen",
    title        = "Specifying Geographic Information - Ontology, Knowledge Representation, and Formal Constraints",
    year         = "2007",
    school       = "Informatics and Mathematical Modelling, Technical University of Denmark, {DTU}",
    address      = "Richard Petersens Plads, Building 321, {DK-}2800 Kgs. Lyngby",
    type         = "",
    note         = "Supervised by Professor Ole Jacobi, Professor Dines Bj{\o}rner and Professor J{\o}rgen Fischer Nilsson, {IMM-DTU}. Thesis not yet published.",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/5223-full.html"
}