مؤلف غير معروف(Corvallis, Or. : Office of the State Climatologist, Climatic Research Institute in cooperation with Agricultural Experiment Station, Hyslop Field Laboratory, Oregon State University, 2013-10-16)
مؤلف غير معروف([Corvallis, Or. : Agricultural Experiment Station, Oregon State University ; [Washington, D.C.] : Agricultural Research Service, USDA, 2013-10-16)