Smith, Freeman M. (Freeman Minson), 1939-, authorSwift, David M. (David Munson), authorNatural Resource Ecology Laboratory, Colorado State University, publisher2007-01-032007-01-031974-03http://hdl.handle.net/10217/16346March 1974born digitaltechnical reportsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.U.S. International Biological ProgramSolar activity -- StatisticsText