Note 121 — Chapter XIX · THE ANALYSIS OF VIRGIN SOILS BY EXTRACTION WITH STRONG ACIDS.
Reading edition
The Supply of Soil Nitrogen, Rep. Cal. Expt. Station, 1892-93, page 68; ibid., 1894-95, page 28; The Recognition of Nitrogen Hungriness in Soils, in Bull. 47, Div. of Chemistry, U.S. Department of Agriculture, 1895; Landw. Presse, No. 53, July 1885. See also for detailed data chapter 8, page 135.