References
- Ensminger , L.E. and Freney , J.R. 1966 . Diagnostic techniques for determining sulphur deficiencies in crops and soils . Soil Sci. , 101 : 283 – 90 .
- Fox , R.L. , Olson , R.A. and Rhoades , H.F. 1964 . Evaluating the sulphur status of soils by plant and soil tests . Soil Sci. Am. Proc , 28 : 243 – 6 .
- Searle , P.L. 1979 . Measurement of adsorbed sulphate in soils ‐ effects of varying soil: extractant ratios and methods of measurement . N.Z.J. Agr. Res , 22 : 287 – 90 .
- Sheard , R.W. and Caldwell , A.G. 1955 . The use of anion‐exchange resins in phosphate fertility studies . Can. J. Agr. Sci. , 35 : 36 – 41 .
- Saunders , W.M.H. 1964 . Extraction of soil phosphate by anion‐exchange membrane . N.Z. J. Agr. Res , 7 : 427 – 31 .
- Blakemore , L.C. , Searle , P.L. and Daly , B.K. 1987 . “ Methods for chemical analysis of soils ” . In NZ Soil Bureau Scientific Report 80
- Fox , R.L. , Hue , N.V. and Parra , A.J. 1987 . A Turbidimetric method for determining phosphate extractable sulphate in tropical soils . Comm. Soil Sci. Plant Anal , 18 : 343 – 57 .
- Johnson , C.M. and Nishita , H. 1952 . Microestimation of sulphur in plant material, soil and irrigation water . Anal. Chem. , 24 : 736 – 42 .