Near Earth objects : hearing before the Subcommittee on Science, Technology, and Space of the Committee on Commerce, Science, and Transportation, United States Senate, One Hundred Eighth Congress, second session, April 7, 2004.
Published: (2016)
Threats from space : a review of U.S. government efforts to track and mitigate asteroids and meteors (part I and part II) : hearing before the Committee on Science, Space, and Technology, House of Representatives, One Hundred Thirteenth Congress, first session, Tuesday, March 19, 2013 and Wednesday, April 10, 2013.
Published: (2013)