Carolingian Commentaries on the Apocalypse by Theodulf and Smaragdus by Francis X. Gumerlock, contains English translations of the commentary on the Book of Revelation by Theodulf of Orleans from the year 810 and of three homilies from the year 812 by Smaragdus of Saint-Mihiel on Rev 1:1-5; Rev 4:1-10; and Rev 14:1-5.

The book is available from Medieval Institute Publications at Western Michigan University (click here) and on Amazon.