Great Britain. Ordnance Survey., O'Flanagan, M., O'Donovan, J., & Ordnance Survey of Ireland. (1926). Sligo letters one vol.: [Letters containing information relative to the antiquities of the county of Sligo, collected during the progress of the Ordnance Survey in 1836].

Great Britain. Ordnance Survey., et al. Sligo Letters One Vol.: [Letters Containing Information Relative to the Antiquities of the County of Sligo, Collected During the Progress of the Ordnance Survey in 1836]. 1926.