Transport for London, Windsor House, 42-50 Victoria Street, London SW1H 0TL, enquire@tfl.gov.uk. "Facts & figures".Pemeliharaan CS1: Banyak nama: authors list (link)
"Annual Report and Statement of Accounts 2011/12"(PDF). TfL. hlm. 71, 74. Diakses tanggal 13 April 2014. Fares revenue on LU was £1,981m... Operating expenditure on the Underground increased by 6.2 per cent to £2,178m