O’donovan 
Tribes and Customs of Hy-Many, Commonly Called O’kelly’s Country [PDF ebook] 
Now First Published Form the Book of Lecan, a Ms. In the Library of the Royal Irish Academy; With a Translation and Notes by John O’donovan

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The following account of the families and customs of Hy-Many is printed from the Book of Lecan, fol. 90 to 92, exactly as it stands in the original, excepting only that the contractions are not retained, and such grammatical marks are introduced as were deemed necessary to render the language intelligible to an Irish scholar not familiar with Ms. abbreviations. The Book of Lecan was compiled from various other Mss. for Gilla losa More Mac Firbis, chief historian of the O’Dowds of Tireragh, in the county of Sligo, about the year 1418 ;but the work has been already so well described by O’Reilly, in his Irish Writers (vol. i. of the Transactions of the Iberno-Celtic Society), that it is not necessary to give any detailed description of it in this place.<br><br>Whether the tract on the customs of Hy-Many was originally composed at the period of the compilation of the Book of Lecan, or transcribed from an older Ms., we are not at present able to decide satisfactorily, as no other copy of it has been discovered, but it is highly probable that it was transcribed, and perhaps abridged, from some Ms. belonging to the territory of Hy-Many.