@article {631, title = {Hydrogen-based microbial ecosystems in the Earth.}, journal = {Science}, volume = {272}, year = {1996}, month = {1996 May 10}, pages = {896b}, issn = {0036-8075}, doi = {10.1126/science.272.5263.896b}, author = {Lovley, D R and Chapelle, F H} }