1. A review of the economic situation of air transport 1957–1967;International Civil Aviation Organisation,1968
2. Jane's All the World's Aircraft, 1905–1968, Great Missenden, Sampson, Low Marston
3. Looking ahead in aeronautics—propulsion;Dawson;Royal Aeronautical Society Journal,1968
4. Methane-fuelled propulsion systems;Weber;Astronautics and Aeronautics,1966
5. Megapolis transportation-high speed ground transportation;Leary;Space Aeronautics,1967