@book{LNCS2283,author={Tobias Nipkow and Lawrence Paulson and Markus Wenzel},
title="Isabelle/HOL --- A Proof Assistant for Higher-Order Logic",
publisher=Springer,series=LNCS,volume=2283,year=2002,
note={\url{http://www.in.tum.de/~nipkow/LNCS2283/}}}
@book{Rogers,author={Rogers},
title="Theory of recursive functions and effective computatibility",
year=1967}
@book{Soare,author={Soare},
title="Recursively enumerable sets and degrees",
year=1987}


