Bandersnatch: C.S. Lewis, J.R.R. Tolkien, and the Creative Collaboration of the Inklings

The Lord Of The Rings: A Reader's Companion

On Writing and Worldbuilding: Volume I

Snape: The definitive analysis of Hogwarts's mysterious potions master (The Unofficial Harry Potter Character Series)

The Art Of The Hobbit By J.r.r. Tolkien

The Outlandish Companion (Revised and Updated): Companion to Outlander, Dragonfly in Amber, Voyager, and Drums of Autumn

The Fellowship: The Literary Lives of the Inklings: J.R.R. Tolkien, C. S. Lewis, Owen Barfield, Charles Williams

Ring Legends of Tolkien (7) (Tolkien Illustrated Guides)

Lord of the Rings and the Eucharist

The Dark Powers of Tolkien (5) (Tolkien Illustrated Guides)