APA (7th ed.) Citation

Great Britain. Ordnance Survey. (1901). Ordnance Survey of Ireland. Ordnance Survey.

Chicago Style (17th ed.) Citation

Great Britain. Ordnance Survey. Ordnance Survey of Ireland. Southampton: Ordnance Survey, 1901.

MLA (8th ed.) Citation

Great Britain. Ordnance Survey. Ordnance Survey of Ireland. Ordnance Survey, 1901.

Warning: These citations may not always be 100% accurate.