NASA's First 50 Years: Historical Perspectives; NASA 50th Anniversary Proceedings : Historical Perspectives; NASA 50th Anniversary Proceedings

New (perfect condition)

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Pages are intact and may have minimal notes and/or highlighting or folds.

Good (clean condition)

All pages and the cover is intact. The spine may show signs of wear. Pages include notes and/or highlighting.

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All pages and the cover is intact. Pages include considerable notes in pen or highlighter, but the text is not obscured.