Singh, Y. (2018). Environmental Science. New Age International Publishers.
Chicago-čujuhus (17. p.)Singh, Y.K. Environmental Science. NEW DELHI: New Age International Publishers, 2018.
MLA-čujuhus (9. p.)Singh, Y.K. Environmental Science. New Age International Publishers, 2018.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.