APA-ийн эшлэл(7 дахь хэвлэлт)

(2000). Percentage of Higher Education Institutions Offering Distance Education. U.S. Department of Education.

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

Percentage of Higher Education Institutions Offering Distance Education. U.S. Department of Education, 2000.

MLA -ийн эшлэл (9 дэх хэвлэлт)

Percentage of Higher Education Institutions Offering Distance Education. U.S. Department of Education, 2000.

Анхааруулга: Эдгээр ишлэлүүд үргэлж 100% үнэн зөв биш байж магадгүй.