1. Optimum soil and plant nutrient levels for petunias;Carlson;Mich. Florist Rev.,1972
2. Studies on the influence of nitrogen, phosphorous and potassium nutrition on nutrient uptake, growth, flower production and seed yield of Petunia hybrida Vilm;Elengonan;Mysore J. Agric. Sci.,1977
3. Potassium nutrition of deciduous fruits;Forshey;HortScience,1969
4. The water culture method for growing plants without soil;Hoagland;Univ. Calif. Agric. Exp. Stn. Circ.,1950
5. Calcium requirement for penetration of sub-soils by primary cotton roots;Howard,1965