¹Mac An Bhaird, Ferghal Óg, and L. McKenna. "Poem to Aodh Ruadh ó Domhnaill." The Irish Monthly 48.567 (1920): 481-85. The text quoted is an excerpt.

²The plaque commemorating the traditional site of the inauguration stone on the Rock of Doon had been vandalized when we made our visit in 1999. The plaque that appears in the VR tour is a composite image in which the damage has been repaired.

³"O'Donnell Coat of Arms and Family History." Araltis - the Internet Heraldry Store. Web. 06 June 2012. <http://www.araltas.com/features/odonnell/>.
See Wikipedia for a listing of the Kings of Tír Chonaill. The earliest printed account of the association between the Rock of Doon and inauguration ceremonies is found in the Post Chaise Companion of 1803. (FitzPatrick, Elizabeth. Royal Inauguration in Gaelic Ireland C. 1100-1600: A Cultural Landscape Study. Woodbridge, Suffolk, UK: Boydell, 2004. 185.)

⁴"O'Donnell Coat of Arms and Family History." Araltis - the Internet Heraldry Store. Web. 06 June 2012. <http://www.araltas.com/features/odonnell/>.
"Like many of the ruling families at that time, they occupied themselves in tribal conflict, mostly attacking their kinsmen, the O'Neills."

⁵Gerald of Wales (Giraldus Cambrensis), and John J. O'Meara. The History and Topography of Ireland. Harmondsworth: Penguin, 1985. 110.
Giraldus was no friend of Ireland, being from a prominent settler family, and his Topographia Hibernica was filled with many fanciful and derogatory references to the native Irish. In the seventeenth century, scholar Geoffrey Keating called it "'a malicious unwarranted lie." However some modern scholars have a more receptive view of the Cambrensis account of the inauguration rite, as they've found "the horse sacrifice associated with kingship rituals among many of the Indo-European peoples [and] ... there is evidence to suggest that even at this late date [1188] a symbolic bath may have formed part of the ceremonies..." (Ó Canann, Tomás G. "Carraig an Dúnáin: Probable Ua Canannáin Inauguration Site." The Journal of the Royal Society of Antiquaries of Ireland 133 (2003): 43-44.)
FitzPatrick claims that reported folklore of the described ritual "is probably a grambled version of Gerald of Wales' written account, but the association of that rite with Carraig an Duin is solely the outcome of local tradition." (FitzPatrick, Elizabeth. Royal Inauguration in Gaelic Ireland C. 1100-1600: A Cultural Landscape Study. Woodbridge, Suffolk, UK: Boydell, 2004. 184.)

⁶O'Donovan, John, and Michael O'Flanagan. Letters Containing Information Relative to the Antiquities of the County of Donegal, Collected during the Progress of the Ordnance Survey in 1835. Vol. 5. Bray, 1927. 53+.
O'Donovan was told by an old O'Donnell gentleman that the inauguration stone in the Kilmacrennan church was "destroyed by a Mr. Mac Swine, who having changed his religion, became a violent hater of everything Irish. He tore down a great part of the old Church to obtain building materials and destroyed all the ornamented stones in the neighbourhood."
Another author suggests that the most significant medieval O'Donnell inauguration site was not The Rock of Doon but rather was at Carraig an Dunain, close to Donegal town. (Ó Canann, Tomás G. "Carraig an Dúnáin: Probable Ua Canannáin Inauguration Site." The Journal of the Royal Society of Antiquaries of Ireland 133 (2003): 42.)
Elizabeth FitzPatrick notes that traditions of the Rock of Doon's use for royal ritual are "based on complex local folktales recorded and reiterated from the beginning of the nineteenth century onwards." ( (FitzPatrick, Elizabeth. Royal Inauguration in Gaelic Ireland C. 1100-1600: A Cultural Landscape Study. Woodbridge, Suffolk, UK: Boydell, 2004. 184.)
More details of the inauguration rite may be found here.

⁷Archdall, Mervyn. Monasticon Hibernicum, Or, An History of the Abbeys, Priories, and Other Religious Houses in Ireland.... Dublin: Printed for Luke White, 1786. 201. Read online here.

⁸FitzPatrick, Elizabeth. Royal Inauguration in Gaelic Ireland C. 1100-1600: A Cultural Landscape Study. Woodbridge, Suffolk, UK: Boydell, 2004. 111-112.
The author believes that the Rock of Doon may well have served for the inauguration of the O'Donnells, at least until 1258 when the bishop of Raphoe summoned Domhnall Og Ó Domhnaill to be inaugurated in Raphoe cathedral. In subsequent years the ceremony was transferred, at least in part, to the church of Kilmacrennan.

⁹"Sir Cahir O'Doherty's Rebellion 1608." Ask About Ireland. Web. 07 June 2012. <http://www.askaboutireland.ie/reading-room/history-heritage/history-of-ireland/the-ulster-plantation/sir-cahir-odohertys-rebel/>.
O'Doherty's original English patron was a military officer, Sir Henry Dowcra. He was replaced by Sir George Paulet, who mistrusted O'Doherty, and enraged the Irishman by punching him in the face. Paulet was killed during O'Doherty's siege of Derry.

¹⁰Ó Canann, Tomás G. "Carraig an Dúnáin: Probable Ua Canannáin Inauguration Site." The Journal of the Royal Society of Antiquaries of Ireland 133 (2003): 55-57.
The author quotes O'Donovan, whose informant "'shewed us the very spot where Sir Cahir O'Doherty was killed, and the rock at which his members [body parts] were boiled in a cauldron!'"
Another account holds that Sir Cahir's death was due not to battle but to the treachery of his own companions. (Archdall, Mervyn. Monasticon Hibernicum, Or, An History of the Abbeys, Priories, and Other Religious Houses in Ireland.... Dublin: Printed for Luke White, 1786. 201.)

¹¹Kinahan, G.H. "Donegal Folk-Lore." The Folk-lore Journal 3.3 (1885): 276.

¹²Gallagher, Charles, "Rock of Doon and Doon Well." Personal Interview. 28 June 1999.

¹³Hutton, Ronald. The Pagan Religions of the Ancient British Isles: Their Nature and Legacy. Oxford, UK: B. Blackwell, 1991. 173.
The Brennemans have described such a sacred marriage to the land by the ruler: "The king or chieftain, then, was married to the goddess of the place, his tuath, through ritual acts at the well. This place" was defined by its natural configurations, through which its power emanated. Because the chieftain was married to this actual place, it was not possible to take land from others through warring activities. Rather, he could take hostages in the form of powerful persons; but the marriage of chief to place is never broken, and its center remained the sacred spring, site of the inauguration ritual." (Brenneman, Walter L., and Mary G. Brenneman. Crossing the Circle at the Holy Wells of Ireland. Charlottesville: University of Virginia, 1995. 36.)

¹⁴"Doon Mass Rock In County Donegal." Your Irish. Web. 07 June 2012. <http://www.yourirish.com/doon-mass-rock>.
Caesar Otway's nineteenth-century informant at the Rock of Doon spoke of the "difficulties the friar encountered in his attempts to bless the well and how its sanctification ensured that the fairies of the Rock would never return." (FitzPatrick, Elizabeth. Royal Inauguration in Gaelic Ireland C. 1100-1600: A Cultural Landscape Study. Woodbridge, Suffolk, UK: Boydell, 2004. 186.)

¹⁵"Doon Well." Finn Valley Places. Web. 07 June 2012. <http://www.finnvalley.ie/places/doon/well.html>.
The author writes, "Up to four decades ago, whole train-loads of pilgrims for Doon Well were there every Sunday throughout the summer months, from places as far apart as Derry and Burtonport, and all points in between. To be there on such an occasion, with hundreds of all ages, engaged devoutly in the turas [procession], was to see an impressive and devotional spectacle."

¹⁶Brenneman, Walter L., and Mary G. Brenneman. Crossing the Circle at the Holy Wells of Ireland. Charlottesville: University of Virginia, 1995. 48-52.
The authors describe the Doon Well "rag tree" as "small, only five and one-half feet tall, but it is completely covered with all manner of clooties so that it appears to be bending under the pain and sickness of all the world." The items left on a rag tree are also referred to as "clooties." Charles Gallagher, in the video interview on the page, notes that pilgrims no longer leave their crutches and canes (sticks) at the well: "There'd be more crutches and sticks there in my young days. They'd be over as far as your car. But, crutches and sticks! There's nobody on crutches and sticks anymore. They're gettin' their hips done, and their legs done, and their ankles done. They don't need sticks anymore."

¹⁷A video of a Catholic Mass being performed in 1999 at the Tawley Mass Rock in Co. Sligo may be seen on this page in Voices from the Dawn. More information about the Doon Mass Rock is here.

¹⁸Gallagher.