The 90 Day Review
The Report of the 90-Day Study on Human Exploration of the Moon and Mars, better known as "The 90 Day Review" was published in November 1989. It was the basis of President George H.W. Bush's space vision called the Space Exploration Initiative/SEI.
Planetary Surface Systems
Robert Zubrin of the Mars Society takes a critical view to the 90 Day Review believing that it was filled with too much pork barrel politics for the aerospace industry and that it was too wasteful. As a result, he did his own research and created the Mars Direct concept, and later formed the Mars Society to advocate his concept.