Hoyt, J. (1964). Man and the earth. Prentice Hall.
Lua i Stíl Chicago (17ú heag.)Hoyt, Joseph. Man and the Earth. Englewood Cliffs: Prentice Hall, 1964.
Lua MLA (9ú heag.)Hoyt, Joseph. Man and the Earth. Prentice Hall, 1964.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.