Dark tower king

Stephen King's the Dark Tower: Beginnings Omnibus

Stephen King's the Dark Tower: The Gunslinger Omnibus

Stephen King's the Dark Tower: The Drawing of the Three Omnibus

Robin Furth: Stephen King's The Dark Tower: Complete Concordance

The Road to the Dark Tower

Stephen King: Dark Tower I: The Gunslinger

Stephen King: Dark Tower I

Bev Vincent: The Dark Tower Companion: A Guide to Stephen King's Epic Fantasy