"Some things the experiment stations have found out about phosphorus, nitrogen, potassium, and the use of commercial fertilizers."; "Dustman, Robert B. (Robert Barclay), 1892-"; "Potassium.", "Phosphorus.", "Nitrogen.", "Fertilizers."; "Dustman, Robert B. (Robert Barclay), 1892-"; "1918"; "

Serial issue. Issued as: West Virginia University. College of Agriculture. Extension Department. Agricultural summary, no. 7 (1918:June).

"; ""; "P19005"; "pec"; "Phosphorus.", "Fertilizers.", "Nitrogen.", "Potassium."; "14256"; .