Guasti, C. A. (2001). Earth: An oasis of life. Reader's Digest.
Chicago-čujuhus (17. p.)Guasti, Carol A. Earth: An Oasis of Life. Pleasantville: Reader's Digest, 2001.
MLA-čujuhus (9. p.)Guasti, Carol A. Earth: An Oasis of Life. Reader's Digest, 2001.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.