specialised fact in the Record theory should not be appear in proofs discovered by sledgehammer
@string{CUP="Cambridge University Press"}
@string{LNCS="Lect.\ Notes in Comp.\ Sci."}
@string{Springer="Springer-Verlag"}
@book{HuthRyan,author="Michael Huth and Mark Ryan",
title={Logic in Computer Science},publisher=CUP,year=2004}
@manual{Krauss,author={Alexander Krauss},
title={Defining Recursive Functions in Isabelle/HOL},
note={\url{http://isabelle.in.tum.de/doc/functions.pdf}}}
@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}
@manual{IsarRef,author={Makarius Wenzel},
title={The Isabelle/Isar Reference Manual},
note={\url{http://isabelle.in.tum.de/doc/isar-ref.pdf}}}