Oxford University Press, 1996. No bibliographies and few cross references, but very extensive coverage of the full range of Irish literature. Strayer, Joseph R., gen. Dictionary of the Middle Ages . A major reference source in this area.
Bibliographies are mostly in English.
Slender but useful atlas covering the complete range of Irish history. Very useful for understanding topographical relationships. W.T.H. Jackson, ed. and G. Stade, ed. in chief. A collection of lengthy signed biographical and critical articles about major European writers. Each article includes a selected bibliography.