Cita APA (7th ed.)
Napitupulu, W. P. (1978). Non-formal education strategies and management. UNESCO.
Cita Chicago (17th ed.)
Napitupulu, W. P. Non-formal Education Strategies and Management. Bangkok: UNESCO, 1978.
Cita MLA (9th ed.)
Napitupulu, W. P. Non-formal Education Strategies and Management. UNESCO, 1978.
Atenció: Aquestes cites poden no estar 100% correctes.