The Complete Peerage of England, Scotland, Ireland, and the United Kingdom @ "Offaly" x, 10-20
The cited information was published by The St. Catherine Press, Ltd., , England, 1910-1959, 13 v. in 14, (Ref: "Offaly" x, 10-20) The author/originator was Cokayne, George Edward, Vicary Gibbs (ed.).