Feather, Clive (15 November 2014). "Vertical Transport". Clive's Underground Line Guides. Retrieved 11 December 2015.
"CULG - Bakerloo Line". Davros.org. Clive's UndergrounD Line Guides. 20 June 2017. Retrieved 14 July 2017.
Feather, Clive (27 January 2015). "Northern line". Clive's Underground Line Guides. Archived from the original on 8 December 2015. Retrieved 1 December 2015.
Feather, Clive (30 December 2014). "Bakerloo line". Clive's Underground Line Guides. Archived from the original on 8 December 2015. Retrieved 2 December 2015.
Feather, Clive (27 January 2015). "Northern line". Clive's Underground Line Guides. Archived from the original on 8 December 2015. Retrieved 1 December 2015.
Feather, Clive (30 December 2014). "Bakerloo line". Clive's Underground Line Guides. Archived from the original on 8 December 2015. Retrieved 2 December 2015.