1. A.O.A.C., 1970. Association of Official Analytical Chemists, Washington, Ed. II, p. 934.
2. On the comparative allocation of biomass, energy, and nutrients in plants;Abrahamson;Ecology,1982
3. Effect of long-term application of fertilizers and organic and inorganic amendments under continuous cropping on soil physical and chemical properties in an Alfisol;Acharya;Indian J. Agric. Sci.,1988
4. Soybean and corn rooting in south-western Minnesota. II. Root distribution and related water inflow;Allmaras;Soil Sci. Soc. Am. Proc.,1975
5. A new handheld penetrometer for soil studies;Anderson;J. Soil Sci.,1980