Railway Letter Stamps and Labels

Bibliography
David Potter, Catalogue of Great Britain Railway Letter Stamps 1957-1970 (Railway Philatelic Group, 1st Edition 1970)
David Potter, Catalogue of Great Britain Railway Letter Stamps 1957-1972 (Railway Philatelic Group, 2nd Edition 1973)
David Potter, Catalogue of Great Britain Railway Letter Stamps 1957-1976 (Railway Philatelic Group, 3rd Edition 1977)
David Potter and Peter Johnson, Great Britain Railway Letter Stamps 1957-1980: A Handbook & Catalogue (Railway Philatelic Group, 4th Edition 1981)
David Potter and Peter Johnson, Great Britain Railway Letter Stamps: A Handbook & Catalogue 1957-1985 (Railway Philatelic Group, 5th Edition 1986)
Neill Oakley, Great Britain & Ireland Railway Letter Stamps 1957-1988 (Railway Philatelic Group, 6th Edition 1989)
Neill Oakley, Great Britain & Ireland Railway Letter Stamps 1957-1992 (Railway Philatelic Group, 7th Edition 1993)
Neill Oakley, Great Britain & Ireland Railway Letter Stamps 1957-1998 (Railway Philatelic Group, 8th Edition 1999)
Neill Oakley and Frank J. Wilson, Great Britain & Ireland Railway Letter Stamps 1957-2007 (Railway Philatelic Group, 9th Edition 2008)