Title: Dune: Legends, Heroes, Schools: (The Butlerian Jihad, The Machine Crusade, The Battle of Corrin, Paul of Dune, The Winds of Dune, Sisterhood of Dune, Mentats of Dune, Navigators of Dune), Author: Brian Herbert
Title: Observers and Navigators: And Other Non-Pilot Aircrew in the RFC, RNAS and RAF, Author: C.G. Jefford