Wright Richard T. (2011). Environmental science: Toward a sustainable future. PHI Learning.
Chicago-čujuhus (17. p.)Wright Richard T. Environmental Science: Toward a Sustainable Future. New Delhi: PHI Learning, 2011.
MLA-čujuhus (9. p.)Wright Richard T. Environmental Science: Toward a Sustainable Future. PHI Learning, 2011.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.