National Research Council (U.S.). Space Studies Board & ebrary, Inc. (2008). Opening new frontiers in space: Choices for the next new frontiers : announcement of opportunity. National Academies Press.
Chicago-referens (17:e uppl.)National Research Council (U.S.). Space Studies Board och Inc ebrary. Opening New Frontiers in Space: Choices for the Next New Frontiers : Announcement of Opportunity. Washington: National Academies Press, 2008.
MLA-referens (9:e uppl.)National Research Council (U.S.). Space Studies Board och Inc ebrary. Opening New Frontiers in Space: Choices for the Next New Frontiers : Announcement of Opportunity. National Academies Press, 2008.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.