1. Cooper, H. R., Nitrogen utilisation in tea. Indian Tea Assoc. Memo.6 (1964).
2. Dutta, S. K., Manures in tea. Two Bud6, 9–14 (1959).
3. Faizullah, M., Hasan, K. A. and Ali, M. M., Effect of NPK on young tea. Tea J. Pak.4, 18–26 (1966).
4. Jackson, M. L., Soil chemical analysis. Prentice-Hall, Inc. Englewood Cliffs. N.J. (1965).
5. Jourbitzky, S. I. and Strauber, D. V., Foliar diagnosis of tea plant. Nitrogen and potassium status. Fertilite26, 3–6 (1966).