U.S. Geological Survey Bulletin
By Gilpin R. Robinson (Jr.), Robert B. Jacobson, Sarah Beanland, Frank Gardner Lesure, Malcolm M. Clark, J. I. Marlowe, Stephen J. Colucci, N. K. Foley, Steven Emil Greco, Jack McGeehin, Sandra H. B. Clark, Elizabeth D. Cron, Carolyn E. Carr, John M. Harper, Alan D. Howard, J. Steven Kite, Ron C. Linton, Andrew J. Miller, Douglas J. Parkinson