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3. Blaisdell , R. Conant , R. Dick , W. Dobermann , A. Izaurralde , C. Ransom , M. Rice , C. Robertson , P. Stuth , J. Thompson , M. Recommended procedures for collecting, processing, and analyzing soil samples in CASMGS research plots http://www.casmgs.colostate.edu/vignette/448_8___recommended%20procedures.pdf 2003
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