@InProceedings{HC96-DISCO,
    Author       = "Homann, K. and Calmet, J.",
    Year         = "1996",
    Title        = "{Structures for Symbolic Mathematical Reasoning and
                    Computation}",
    Editor       = "Calmet, J. and Limongelli, C.",
    BookTitle    = "{Proceedings of the International Symposium on the Design
                    and Implementation of Symbolic Computation Systems}",
    Place        = "Karlsruhe, Germany",
    Series       = "Lecture Notes in Computer Science",
    Number       = "1128",
    Pages        = "216-227",
    Publisher    = "Springer-Verlag",
    Comment      = "TPTPRefForResults"
}

@Book{HC96,
    Author       = "Hughes, G. and Cresswell, M.",
    Year         = "1996",
    Title        = "{A New Introduction to Modal Logic}",
    Publisher    = "Methuen and Co",
    Comment      = "TPTPRef"
}