@Article{OS08,
    Author       = "Ortner, V. and Schirmer, N.",
    Year         = "2008",
    Title        = "{BDD Normalisation}",
    Journal      = "Archive of Formal Proofs",
    Note         = "{http://isa-afp.org/entries/BDD.shtml}",
    Comment      = "TPTPRef"
}