US Geological Survey Library
(18)
New Jersey Geological Survey
(9)
Geological Survey of Pennsylvania
(4)
Kentucky Geological Survey
(4)
United States Geological Survey
(4)
Geological Survey of Canada
(3)
Maryland Geological Survey
(3)
Massachusetts Geological Survey
(3)
Arkansas Geological Survey
(2)
Geological Survey (COR)/ Interior Department (COR)/ Mines Bureau (COR)
(2)
Geological Survey Willard Hayes (U S.)
(2)
Geological Survey of Alabama
(2)
Geological Survey of Britain
(2)
Geological Survey of Dwight Whitney
(2)
Geological Survey of William Dawson
(2)
John Arthurs (Geological Survey of Northern Ireland)
(2)
Marc (Population Ecologist Kery Swiss Ornithological Institute Switzerland),Royle, J. Andrew (Research Statistician, U.S. Geological Survey, Patuxent Wildlife Research Center, Laurel, MD, USA)
(2)
Washington Geological Survey
(2)