S121E08333 - STS-121 - Earth view taken during STS-121.

Chicago citation style
National Aeronautics and Space Administration. Lyndon B. Johnson Space Center. 2/17/1973. S121E08333 - STS-121 - Earth view taken during STS-121.. 1981-04-12/2011-07-21. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/23441540. (Accessed September 24, 2018.)
APA citation style
National Aeronautics and Space Administration. Lyndon B. Johnson Space Center. 2/17/1973, (1981-04-12/2011-07-21) S121E08333 - STS-121 - Earth view taken during STS-121.. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/23441540
MLA citation style
National Aeronautics and Space Administration. Lyndon B. Johnson Space Center. 2/17/1973. Retrieved from the Digital Public Library of America <http://catalog.archives.gov/id/23441540>.
Note: These citations are programmatically generated and may be incomplete.