P. Owuor, S. Msomba, D. Kamau, M. Uwiman, and C. Muhoza, “Effects of location of production, nitrogenous fertilizer rates and plucking intervals on tea clone TRFK 6/8 tea in East Africa: I. yields”, IJTS, vol. 10, no. 03 and 04, pp. 14-24, Dec. 2014.