E. Graven

Effect of Soil Type and Nutrient Status on the Yield and Composition of Tagetes Oil (Tagetes minuta L.)

J. B. Gardner, E. H. Graven, L. Webber, 1991 .

Effects of phosphate carrier, phosphate placement, and level of lime application on plant growth on two oxisols in natal*

E. H. Graven, K. Nathanson, I. G. Wiseman, 1972 .