Flying Beyond the Stall by Douglas A. Joyce
Publisher: NASA 2014
Number of pages: 429
The X-31 was unique in the world of experimental or X-airplanes. It was the only X-plane that was designed, manufactured, and flight tested as an international effort; a joint effort of the United States and Germany. It also was the only X-plane that supported two separate test programs.
Engineering Aerospace Aeronautics & Astronautics