^Mittleman, Josh. Concerning the name Deirdre. Quote: "Early Gaelic (aka Old Irish) is the form of Gaelic used in Ireland and parts of Scotland from roughly 600 - 900 AD. Middle Gaelic (aka Middle Irish) was used from roughly 900 - 1200 AD, while Common Classical Gaelic (aka Early Modern Irish, Common Literary Gaelic, etc.) was used from roughly 1200 - 1700 AD". Medieval Scotland. Retrieved 13 February 2013.
^Breatnach, Liam (1994). "An Mheán-Ghaeilge". In K. McCone, D. McManus, C. Ó Háinle, N. Williams, and L. Breatnach (eds.). Stair na Gaeilge in ómós do Pádraig Ó Fiannachta (in Irish). Maynooth: Department of Old Irish, St. Patrick's College. pp. 221–333. ISBN0-901519-90-1.
^Clancy, Thomas Owen (2000). "Scotland, the 'Nennian' recension of the Historia Brittonum, and the Lebor Bretnach". In Simon Taylor (ed.). Kings, Clerics and Chronicles in Scotland, 500-1297. Dublin & Portland: Four Courts Press. pp. 87–107. ISBN1-85182-516-9.