STANLEY, S. M. (1977). Earth and life through time. W.H. Freeman.
Lua i Stíl Chicago (17ú heag.)STANLEY, Steven M. Earth and Life Through Time. W.H. Freeman, 1977.
Lua MLA (8ú heag.)STANLEY, Steven M. Earth and Life Through Time. W.H. Freeman, 1977.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.