Coldeway, D. O., & Spencer, R. E. (1980). The measurement of attrition and completion in distance learning courses. Athabasca University.
Цитирование в стиле Чикаго (17-е изд.)Coldeway, Dan O., и Robert E. Spencer. The Measurement of Attrition and Completion in Distance Learning Courses. Edmonton, Alta.: Athabasca University, 1980.
Цитирование MLA (8-е изд.)Coldeway, Dan O., и Robert E. Spencer. The Measurement of Attrition and Completion in Distance Learning Courses. Athabasca University, 1980.
Предупреждение: эти цитированмия не могут быть всегда правильны на 100%.