Ludwig, G. H. (2011). Opening space research: Dreams, technology, and scientific discovery. American Geophysical Union.
Lua i Stíl Chicago (17ú heag.)Ludwig, George H. Opening Space Research: Dreams, Technology, and Scientific Discovery. Washington, DC: American Geophysical Union, 2011.
Lua MLA (9ú heag.)Ludwig, George H. Opening Space Research: Dreams, Technology, and Scientific Discovery. American Geophysical Union, 2011.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.