Παραπομπή APA

Ward, B. (1972). Only the earth: The care and maintenance of a small planet. New York: Pengiun Books.

Παραπομπή Chicago Style

Ward, Barbara. Only the Earth: The Care and Maintenance of a Small Planet. New York: Pengiun Books, 1972.

Παραπομπή MLA

Ward, Barbara. Only the Earth: The Care and Maintenance of a Small Planet. New York: Pengiun Books, 1972.

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