Young, A. J., & MacElhone, M. J. (1986). Guidelines for the development of non-formal environmental education: Unesco-UNEP Internat. Environmental Education Programme. Unesco, Division of Science, Techn. and Environmental Education.
Chicago-Zitierstil (17. Ausg.)Young, A. J., und M. J. MacElhone. Guidelines for the Development of Non-formal Environmental Education: Unesco-UNEP Internat. Environmental Education Programme. Paris: Unesco, Division of Science, Techn. and Environmental Education, 1986.
MLA-Zitierstil (9. Ausg.)Young, A. J., und M. J. MacElhone. Guidelines for the Development of Non-formal Environmental Education: Unesco-UNEP Internat. Environmental Education Programme. Unesco, Division of Science, Techn. and Environmental Education, 1986.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.