Semmens, P.W.B.; Goldfinch, A.J. (2003) [2000]. How Steam Locomotives Really Work. Oxford: Oxford University Press. ISBN 978-0-19-860782-3.
Semmens, P.W.B.; Goldfinch, A.J. (2003) [2000]. How Steam Locomotives Really Work. Oxford: Oxford University Press. ISBN 978-0-19-860782-3.