¹Lawlor, H.C. "Some Tentative Deductions Arising from the Study of Three Ancient Monuments in Northern Ireland. 1. The Holestone." The Irish Naturalists' Journal 3.5 (1930): 107-08.
This author's prize-winning essay cites as evidence for the Holestone's ancient importance the fact that the builders of the nearby souterrains did not attempt to use the Holestone in their construction.