The book (published by Wiley, Chichester, 1979, reprinted 1987, 1994) is now available from Cambridge University Press, 2011.
Permission is granted for the material to be freely
downloaded and distributed for instructional non-profit
purposes, from
Reversibility
and Stochastic Networks.
Grateful thanks to Alan Bain,
whose initiative made this possible.
Nicky van Foreest
kindly upgraded the book's djvu
file
to enable searching: free plug-ins available from
DjVu home.