The occurrence of azotobacter in Iowa soils and factors affecting their distribution /
by William P. Martin, R.H. Walker and P.E. Brown.
APA Citation
Martin, W. P., Walker, R. Harper., Brown, P. E. (Percy Edgar). (1937). The occurrence of azotobacter in Iowa soils and factors affecting their distribution. Ames, Iowa: Agricultural Experiment Station, Iowa State College of Agriculture and Mechanic Arts.
MLA Citation
Martin, William P, Rudger Harper Walker, and P. E. (Percy Edgar) Brown. The Occurrence of Azotobacter In Iowa Soils And Factors Affecting Their Distribution. Ames, Iowa: Agricultural Experiment Station, Iowa State College of Agriculture and Mechanic Arts, 1937.
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