Stapp, W. B. (1975). Environmental education: A guide to information sources. Gale Research Company.
Chicago-viite (17. p.)Stapp, William B. Environmental Education: A Guide to Information Sources. Detroit, Michigan: Gale Research Company, 1975.
MLA-viite (9. p.)Stapp, William B. Environmental Education: A Guide to Information Sources. Gale Research Company, 1975.
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