.<ref>Diaries of [//en.wikipedia.org/wiki/George_Turnbull_(civil_engineer) George Turnbull] (Chief Engineer, [//en.wikipedia.org/wiki/East_Indian_Railway_Company East Indian Railway Company]) held at the [//en.wikipedia.org/wiki/Centre_of_South_Asian_Studies Centre of South Asian Studies] at [//en.wikipedia.org/wiki/Cambridge_University Cambridge University], England</ref><ref>'' George Turnbull, C. E .'' pages 110, 121, 122, 125 and 127 of the 437-page memoirs published privately 1893, scanned copy held in the British Library, London on compact disk since 2007</ref>
.<ref name="Ahrons, Faerie Queen">{{cite book|title=The British Steam Railway Locomotive|last=Ahrons|first=E.L.|publisher=[[Ian Allan Publishing|Ian Allan]]|year=1966|volume=I, to 1925|pages=142|ref=Ahrons, British Steam Railway Locomotive|authorlink=E.L. Ahrons}}</ref>
