Ian Horrocks
Department of Computer Science, University of Manchester,
Oxford Road, Manchester, M13 9PL, UK
horrocks@cs.man.ac.uk

Ullrich Hustadt
Department of Computer Science
University of Liverpool
Liverpool L69 7ZF, UK
U.Hustadt@csc.liv.ac.uk

Ulrike Sattler
Department of Computer Science, University of Manchester,
Oxford Road, Manchester, M13 9PL, UK
sattler@cs.man.ac.uk

Renate Schmidt
Department of Computer Science, University of Manchester,
Oxford Road, Manchester, M13 9PL, UK
schmidt@cs.man.ac.uk