* Cambridge (UK) http://www.cl.cam.ac.uk/Research/HVG/Isabelle/dist/ * Munich (Germany) http://isabelle.in.tum.de/dist/ * New Jersey (USA) http://ftp.research.bell-labs.com/dist/smlnj/isabelle/source.html Dave MacQueen * Stanford (USA) ftp://rodin.stanford.edu/pub/smlnj/isabelle/source.html Lal George (?)