Ordnance Survey Northern Ireland One-inch Series : 3rd edition.
Great Britain.Ordnance Survey.
Belfast : Ordnance Survey of Northern Ireland,
[1960-1979].
Relief shown by contour lines, hypsometric tinting and spot heights.
Sheet 1. North Coast (1961 ; 1966 ; 1972 ; 1979) -- Sheet 2. Londonderry (1962 ; 1967 ; 1976) -- Sheet 3. Mid Antrim (1960 ; 1971 ; 1975 ; 1978) -- Sheet 4. Omagh (1963 ; 1968 ; 1978) -- Sheet 5. East Tyrone (1964 ; 1967 ; 1976) -- Sheet 6. Belfast (1963 ; 1967 ; 1971 ; 1976) -- Sheet 7. Enniskillin (1963 ; 1978) -- Sheet 8. Armagh (1962 ; 1968 ; 1976) -- Sheet 9. South Down (1964 ; 1973 ; 1978).
refer to: C20(25), C20(25B).
refer to: 32 (R. Hellyer: 1999).