== Eksterne henvisninger ==
* {{Cite web |last= |first= |title=Piccadilly line facts |url=http://www.tfl.gov.uk/corporate/modesoftransport/londonunderground/keyfacts/13175.aspx |work=www.tfl.gov.uk |publisher=Transport for London |date= |access-date=12. april 2011 |archive-date=10. februar 2014 |archive-url=https://web.archive.org/web/20140210035233/http://www.tfl.gov.uk/corporate/modesoftransport/londonunderground/keyfacts/13175.aspx |url-status=dead }}
* {{Cite web |last= |first= |title=The Piccadilly Line – History |url=http://www.krysstal.com/piccline.html |work=www.krysstal.com |publisher=KryssTal |date= |access-date=12. april 2011}}
* {{Cite web |url=http://www.architecture.com/LibraryDrawingsAndPhotographs/Exhibitionsandloans/VARIBAArchitecturePartnershipexhibitions/UndergroundJourneys/ChangingthefaceofLondonUnderground/ChangingTheFaceOfLondonUnderground.aspx |title=Underground Journeys: Changing the face of London Underground Illustrated history of the Piccadilly line 1920-1930s |work=www.architecture.com |publisher=[[Royal Institute of British Architects]] |date= |access-date=19. februar 2011 |archive-date= 4. maj 2011 |archive-url=https://web.archive.org/web/20110504024645/http://www.architecture.com/LibraryDrawingsAndPhotographs/Exhibitionsandloans/VARIBAArchitecturePartnershipexhibitions/UndergroundJourneys/ChangingthefaceofLondonUnderground/ChangingTheFaceOfLondonUnderground.aspx |url-status=dead }}
Historie Foreninger Organisationer