1. Priorities for British Soil Science;Cooke;J. Soil Sci.,1979
2. Soil analysis methods as used in Iowa State College, Soil Testing Laboratory;Hanway;Iowa State Agric. Bull.,1952
3. Feldspars, olivines, pyroxenes and amphiboles;Huang,1977
4. On the behaviour of non-exchangeable K in soils;Martin;Commun. Soil Sci. Plant Anal.,1985
5. Soil measurement of plant available potassium;McLean,1985