Revisions
Since Mars Direct was initially conceived, it has undergone regular review and development by Zubrin himself, the Mars Society, NASA, Stanford University and others.
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Famous quotes containing the word revisions:
“The lore of our fathers is a fabric of sentences. In our hands it develops and changes, through more or less arbitrary and deliberate revisions and additions of our own, more or less directly occasioned by the continuing stimulation of our sense organs. It is a pale gray lore, black with fact and white with convention. But I have found no substantial reasons for concluding that there are any quite black threads in it, or any white ones.”
—Willard Van Orman Quine (b. 1908)