Klaus Ambos-Spies Benedikt Löwe Wolfgang Merkle Mathematical Theory and Computational Practice, 5th Conference on Computability in Europe, CiE 2009, Heidelberg, Germany, July 19-24, 2009. Proceedings 5635 2009 http://dx.doi.org/10.1007/978-3-642-03073-4 978-3-642-03072-7 CiE Lecture Notes in Computer Science Springer db/conf/cie/cie2009.html