Ward, B., & Dubos, R. J. (1972). Only one earth: The care and maintenance of a small planet (First edition.). Norton & Company.

Ward, Barbara, and René J. Dubos. Only One Earth: The Care and Maintenance of a Small Planet. First edition. New York: Norton & Company, 1972.

Ward, Barbara, and René J. Dubos. Only One Earth: The Care and Maintenance of a Small Planet. First edition. Norton & Company, 1972.