The Book of the Dun Cow

Blurb

The Book of the Dun Cow is a fantasy novel by Walter Wangerin, Jr.. It is loosely based upon the beast fable of Chanticleer and the Fox adapted from the story of "The Nun's Priest's Tale" from Geoffrey Chaucer's Canterbury Tales.
The Book was named The New York Times Best Children's Book of the Year and its first paperback edition won a U.S. National Book Award in the one-year category Science Fiction.
It was later adapted as a musical by Mark St. Germain and Randy Courts, and produced as an Off-Broadway show in 2006 by The Prospect Theater Company.
Wangerin wrote a sequel, The Book of Sorrows.