Geothermal energy :
clean power from the Earth's heat /
by Wendell A. Duffield and John H. Sass.

APA Citation

Duffield, W. A., Sass, J. H. (John Harvey)., Geological Survey (U.S.). (2003). Geothermal energy: clean power from the Earth's heat. Menlo Park, Calif.: U.S. Geological Survey .

MLA Citation

Duffield, Wendell A, J. H. (John Harvey) Sass, and Geological Survey (U.S.). Geothermal Energy: Clean Power From the Earth's Heat. Menlo Park, Calif.: U.S. Geological Survey , 2003.

Warning: These citations may not always be complete (especially for serials).