Cita APA (7a ed.)

Mackenzie, N., Postgate, R., & Scupham, J. (1975). Open learning: Systems and problems in post-secondary education. Unesco.

Cita Chicago Style (17a ed.)

Mackenzie, Norman, Richmond Postgate, y John Scupham. Open Learning: Systems and Problems in Post-secondary Education. París: Unesco, 1975.

Cita MLA (8a ed.)

Mackenzie, Norman, et al. Open Learning: Systems and Problems in Post-secondary Education. Unesco, 1975.