Soil and water conservation research in Puerto Rico, 1938 to 1947
Smith, Richard M., Abruna, Fernando
Soil and water conservation research in Puerto Rico, 1938 to 1947 - Rio Piedras 1955 - 51 p. - No. 124; Puerto Rico Agricult .
Soil and water conservation research in Puerto Rico, 1938 to 1947 - Rio Piedras 1955 - 51 p. - No. 124; Puerto Rico Agricult .