Soil Classification Cline, Marlin G. ; Henderson, J. R. ; Humbert, Roger P. ; Johnsgard, Gordon ; Gardner, Robert A. ; Riecken, Frank F. ; Winters, Eric ; Kellogg, Charles E. Abstract Publication: Soil Science Pub Date: February 1949 DOI: 10.1097/00010694-194902000-00001 Bibcode: 1949SoilS..67...77C