United Nations . Office for Outer Space Affairs. (1992). Planetarium, a challenge for educators: A guidebook published by the United Nations for International Space Year. United Nations.
Chicago Style (17th ed.) CitationUnited Nations . Office for Outer Space Affairs. Planetarium, a Challenge for Educators: A Guidebook Published by the United Nations for International Space Year. New York: United Nations, 1992.
MLA (9th ed.) CitationUnited Nations . Office for Outer Space Affairs. Planetarium, a Challenge for Educators: A Guidebook Published by the United Nations for International Space Year. United Nations, 1992.
Warning: These citations may not always be 100% accurate.