Bibliografia
- Berrill N.J., 1955. Man's Emerging Mind. Dodd, Mead & Co., New York.
- Carson R., 1962. Silent Spring. Houghton Mifflin Company, Boston.
- Leopold A., 1949. A Sand County Almanac, with other Essays on Conservation. Oxford University Press, Round River.
- Mead M., 1957. Toward more vivid utopias. Science, 126: 957–961.
- Van Rensselaer Potter, 1971. Bioethics. Bridge to the future. Prentice-Hall, Englewood Cliffs, N.J.