Robert A. LeMassena, Articulated Steam Locomotives Of North America. Sundance Publications 1979.
CPR built six of these 0-6-6-0s in their Montreal shops during 1909-1911 for use as pushers up Kicking Horse Pass in British Columbia. They were unlike any other articulated locomotives, having all four cylinders located between the driving wheels. They may have been adequate as helpers but by 1917 they had all been retired, rebuilt into 2-10-0s which were much more versatile, being able to be used as road engines as well as helpers.
D M Bain, Canadian Pacific in the Rockies (Volume 8), Published by the Calgary Group of The British Modellers of North America. 1982