Protegiendo la biodiversidadSusan Perkoff Bass, Manuel Ruiz Muller · First published 2001Open the Tome
Proteger la BiodiversiteSusan Perkoff Bass, Manuel Ruiz Muller, Recherches pour le Developpement International Staff · First published 2000Open the Tome
Hard rock miningJames M. McElfish, James M., Jr. Mcelfish, Tobie Bernstein, Susan Perkoff Bass, Elizabeth Sheldon · First published 1996Open the Tome
