@BOOK{NAP754, author = "National Research Council", title = "Planetary and Lunar Exploration: Space Science in the Twenty-First Century -- Imperatives for the Decades 1995 to 2015", isbn = "978-0-309-03885-0", doi = "10.17226/754", url = "https://nap.nationalacademies.org/catalog/754/planetary-and-lunar-exploration-space-science-in-the-twenty-first", year = 1988, publisher = "The National Academies Press", address = "Washington, DC" }