Engel, J. R., Engel, J. G., & Petersen, J. D. (1990). Ethics of environment and development: Global challenge, international response. Tucson: The University of Arizona Press.
Παραπομπή Chicago StyleEngel, J. Ronald, Joan Gibb Engel, and John D. Petersen. Ethics of Environment and Development: Global Challenge, International Response. Tucson: The University of Arizona Press, 1990.
Παραπομπή MLAEngel, J. Ronald, Joan Gibb Engel, and John D. Petersen. Ethics of Environment and Development: Global Challenge, International Response. Tucson: The University of Arizona Press, 1990.
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