Ordnance Survey Northern Ireland Half-inch Series.
Great Britain.Ordnance Survey.
Belfast : Ordnance Survey of Northern Ireland,
1968-1970.
Relief shown by contours, spot heights, and gradient tints. Depths shown by bathymetric isolines.
"Topography based on 1ʺ Third Series, which was revised 1953-1962 (Northern Ireland only)."
"The inclusion of the Republic of Ireland is by permission of the Minister of Finance of the Republic of Ireland."
Index map in bottom margin of each sheet.
"The Irish Grid."
Sheet 1. The North-West -- Sheet 2. The North-East -- Sheet 3. The South-West -- Sheet 4. The South-East.
refer to: 40 (R. Hellyer: 1999).