National Service Center for Environmental Publications NSCEP / U.S. Environmental Protection Agency EPA. Onsite Wastewater Treatment Systems Manual.
Чикаго-гийн эшлэл (17 дахь хэвлэлт)National Service Center for Environmental Publications NSCEP / U.S. Environmental Protection Agency EPA. Onsite Wastewater Treatment Systems Manual.
MLA -ийн эшлэл (9 дэх хэвлэлт)National Service Center for Environmental Publications NSCEP / U.S. Environmental Protection Agency EPA. Onsite Wastewater Treatment Systems Manual.
Анхааруулга: Эдгээр ишлэлүүд үргэлж 100% үнэн зөв биш байж магадгүй.