In 1998, the aviation community published the Airplane Upset Recovery Training Aid, providing pilots and instructors with the academic knowledge on airplane upsets. The latest version of this valuable resource (version 2 November 2008) can be downloaded from the Flight Safety Foundation website.
The supplement “High Altitude Operations: Supplement #1 to the Airplane Upset Recovery Training Aid” can be downloaded from here, as well as a number of presentations on upset recovery briefing and high altitude operations.