Unesco. UNEP International Environmental Programme, Marcinkowski, T. J., Volk, T. L., & Hungerford, H. R. (1990). An environmental education approach to training of middle level teachers: A prototype programme. Unesco.
Chicago-referens (17:e uppl.)Unesco. UNEP International Environmental Programme, Thomas J. Marcinkowski, Trudi L. Volk, och Harold R. Hungerford. An Environmental Education Approach to Training of Middle Level Teachers: A Prototype Programme. Paris: Unesco, 1990.
MLA-referens (9:e uppl.)Unesco. UNEP International Environmental Programme, et al. An Environmental Education Approach to Training of Middle Level Teachers: A Prototype Programme. Unesco, 1990.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.