Gaelic titles and forms of address

This is the first and only book on the subject. 2nd edition of 1997 is
more comprehensive. Published by the Irish Genealogical Press of
Kansas City, MO, USA. Deals with all aspects of the nobiliary structure
of independent Ireland, contrasting with British systems. No monarchist
agenda at all, very understandable and complete as deals with all levels
of the Gaelic system, and how the inheritors of those titles still exist
today though actual rule was long-ago extinguished by conquest. Has
been widely referenced by others for, as said, it is the only book on the
subject and is based on historic Irish Brehon law.