^Brown, David K. (2006). The Way of a Ship in the Midst of the Sea: The Life and Work of William Froude. Periscope Publishing Ltd. p. 113. ISBN1904381405.
^Brown, David K. (2006). The Way of a Ship in the Midst of the Sea: The Life and Work of William Froude. Periscope Publishing Ltd. p. 128. ISBN1904381405.