Atchinson, S. W. (1985). A naturalist's guide to hiking the Grand Canyon. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Atchinson, Stewart W. A Naturalist's Guide to Hiking the Grand Canyon. Englewood Cliffs, New Jersey: Prentice-Hall, 1985.
Lua MLA (9ú heag.)Atchinson, Stewart W. A Naturalist's Guide to Hiking the Grand Canyon. Prentice-Hall, 1985.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.