Sandburg, H. (1958). The wheel of earth. McDowell, Obolensky.
Lua i Stíl Chicago (17ú heag.)Sandburg, Helga. The Wheel of Earth. [New York]: McDowell, Obolensky, 1958.
Lua MLA (8ú heag.)Sandburg, Helga. The Wheel of Earth. McDowell, Obolensky, 1958.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.