@InProceedings{Pfe88,
    Author       = "Pfenning, F.",
    Year         = "1988",
    Title        = "{Single Axioms in the Implicational Propositional
                    Calculus}",
    Editor       = "Lusk, E. and Overbeek, R.",
    BookTitle    = "{Proceedings of the 9th International Conference on
                    Automated Deduction}",
    Place        = "Argonne, USA",
    Series       = "Lecture Notes in Computer Science",
    Number       = "310",
    Pages        = "710 - 713",
    Publisher    = "Springer-Verlag",
    Comment      = "TPTPRef"
}