International Center for the Environment and Public Policy (California Institute of Public Affairs), Sierra Club, International Union for Conservation of Nature and Natural Resources, Trzyna, T. C., Margold, E., & Osborn, J. K. (1996). World directory of environmental organizations: A handbook of national and international organizations and programs -governmental and non-governmental - concerned with protecting the earth's resources (5th ed.). International Center for the Environment and Public Policy, California Institute of Public Affairs Earthscan Publications in cooperation with IUCN-the World Conservation Union and the Sierra Club.
Cytowanie według stylu Chicago (wyd. 17)International Center for the Environment and Public Policy (California Institute of Public Affairs), Sierra Club, International Union for Conservation of Nature and Natural Resources, Thaddeus C. Trzyna, Elizabeth Margold, i Julia K. Osborn. World Directory of Environmental Organizations: A Handbook of National and International Organizations and Programs -governmental and Non-governmental - Concerned with Protecting the Earth's Resources. 5th ed. Sacramento, Calif., London: International Center for the Environment and Public Policy, California Institute of Public Affairs Earthscan Publications in cooperation with IUCN-the World Conservation Union and the Sierra Club, 1996.
Cytowanie według stylu MLA (wyd. 9)International Center for the Environment and Public Policy (California Institute of Public Affairs), et al. World Directory of Environmental Organizations: A Handbook of National and International Organizations and Programs -governmental and Non-governmental - Concerned with Protecting the Earth's Resources. 5th ed. International Center for the Environment and Public Policy, California Institute of Public Affairs Earthscan Publications in cooperation with IUCN-the World Conservation Union and the Sierra Club, 1996.