Sullivan, N. (1964). Pioneer astronomers. Sholastic.
Lua i Stíl Chicago (17ú heag.)Sullivan, Navin. Pioneer Astronomers. New York: Sholastic, 1964.
Lua MLA (9ú heag.)Sullivan, Navin. Pioneer Astronomers. Sholastic, 1964.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.