Environmental improvement; air, water, and soil
Contributors: Graduate School, USDA
Publisher: Graduate School, U.S. Dept. of Agriculture
Place of publication: Washington]
Language: eng
Number of pages: 105
Subjects: Nature; Effect of human beings on; Air; Pollution; Water
Notes: Text of the lectures presented at the lecture series, Enviornmental improvement, U.S. Dept. of Agriculture, May 1966.