Brubaker, S. (1972). To live on earth: Man and his environment in perspective. Johns Hopkins Press for Resources for the Future.
Cita Chicago (17th ed.)Brubaker, Sterling. To Live on Earth: Man and His Environment in Perspective. Baltimore: Johns Hopkins Press for Resources for the Future, 1972.
Cita MLA (9th ed.)Brubaker, Sterling. To Live on Earth: Man and His Environment in Perspective. Johns Hopkins Press for Resources for the Future, 1972.
Atenció: Aquestes cites poden no estar 100% correctes.