See also references for related subjects.
Fitzpatrick, Siobhán, “Seosamh Ó Longáin and the Royal Irish Academy”, in: Pádraig Ó Macháin, and Sorcha Nic Lochlainn (eds),
Leabhar na Longánach: the Ó Longáin family and their manuscripts, Cork: Clo Torna, 2018. 117–138.
Sharpe, Richard, “Appendix 2: Manuscripts of the Betham collection as appearing in the 1847 valuation-list”, in: Pádraig Ó Macháin, and Sorcha Nic Lochlainn (eds),
Leabhar na Longánach: the Ó Longáin family and their manuscripts, Cork: Clo Torna, 2018. 347–358.
Sharpe, Richard, “The manuscripts of Micheál Óg Ó Longáin that were sold to Sir William Betham”, in: Pádraig Ó Macháin, and Sorcha Nic Lochlainn (eds),
Leabhar na Longánach: the Ó Longáin family and their manuscripts, Cork: Clo Torna, 2018. 259–332.
McGuire, James [ed.], and James Quinn [ed.],
Dictionary of Irish biography, online ed., Online: Royal Irish Academy, Cambridge University Press, 2009–present. URL: <
https://www.dib.ie>.
Ní Úrdail, Meidhbhín,
The scribe in eighteenth- and nineteenth-century Ireland: motivations and milieu, Studien und Texte zur Keltologie, 3, Münster: Nodus Publikationen, 2000.
Preliminaries; 1. Introduction; 2. The Ó Longáin scribal family; 3. Material contained in the Ó Longáin manuscripts; 4. Script and print: interactions and reciprocal influences; 5. Conclusion; Appendix: manuscript reproductions; Bibliography and indexes.
Phair, P. B., “Sir William Betham’s manuscripts”,
Analecta Hibernica 27 (1972): 1–99.
Phair, P. B., “Betham and the older Irish manuscripts”,
Journal of the Royal Society of Antiquaries of Ireland 92:1 (1962): 75–78.
OʼCurry, Eugene, Seosamh Ó Longáin, and John O'Beirne Crowe, “[Unpublished catalogue of the Betham collection of manuscripts in the Royal Irish Academy]”, 5 vols, unpublished, 1851?. Manuscript.
Vols 1-2 (RIA MS 67 E 15-16) by Eugene O’Curry -- vols 3–4 (RIA MS 67 E 17-18) by Seosamh Ó Longáin -- vol. 5 (RIA MS 67 E 19) by J. O’Beirne Crowe. The date of writing is currently unverified.
Later, secondary hand:
scribes:Ó Cléirigh (Seán) ... d. 1846
Betham, William,
The Gael and Cymbri, or an inquiry into the origin and history of the Irish Scoti, Britons, and Gauls, and of the Caledonians, Picts, Welsh, Cornish, and Bretons, Dublin, 1834.
Betham, William,
Irish antiquarian researches, 2 vols, Dublin: William Curry, Jun. & Co., 1826–1827.
Internet Archive – vols 1-2: <link> Internet Archive – vols 1-2, originally from Google Books: <link> Internet Archive – vol. 1, originally from Google Books: <link> Internet Archive – vol. 2, originally from Google Books: <link>
Betham, William,
Irish antiquarian researches, 2 vols, vol. 2, Dublin: William Curry, Jun. & Co., 1827.
Internet Archive – Originally from Google Books: <link> Digitale-sammlungen.de: <link> Digitale-sammlungen.de: View in Mirador
Betham, William,
Irish antiquarian researches, 2 vols, vol. 1, Dublin: William Curry, Jun. & Co., 1826.