Environmental Protection Agency. Parameters of water quality , interpretation and standards.
Chicago-čujuhus (17. p.)Environmental Protection Agency. Parameters of Water Quality , Interpretation and Standards.
MLA-čujuhus (9. p.)Environmental Protection Agency. Parameters of Water Quality , Interpretation and Standards.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.