Wijewardena, J.D.H. and Amarasiri, S.L., 1997. Long-term use of potassium fertilizer for vegetable crops in the upcountry intermediate zone. Journal of the National Science Foundation of Sri Lanka, 25(1), pp.59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena JDH, Amarasiri SL. Long-term use of potassium fertilizer for vegetable crops in the upcountry intermediate zone. Journal of the National Science Foundation of Sri Lanka. 1997;25(1):59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena, J. D. H., & Amarasiri, S. L. (1997). Long-term use of potassium fertilizer for vegetable crops in the upcountry intermediate zone. Journal of the National Science Foundation of Sri Lanka, 25(1), 59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena JDH and Amarasiri SL, ‘Long-term Use of Potassium Fertilizer for Vegetable Crops in the Upcountry Intermediate Zone’ (1997) 25 Journal of the National Science Foundation of Sri Lanka 59 DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena, J.D.H., and S.L. Amarasiri. 1997. “Long-term Use of Potassium Fertilizer for Vegetable Crops in the Upcountry Intermediate Zone”. Journal of the National Science Foundation of Sri Lanka 25 (1): 59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena, J.D.H., and S.L. Amarasiri. “Long-term Use of Potassium Fertilizer for Vegetable Crops in the Upcountry Intermediate Zone”. Journal of the National Science Foundation of Sri Lanka 25, no. 1 (1997): 59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019

Wijewardena, J. D. H.and S. L. Amarasiri. “Long-term Use of Potassium Fertilizer for Vegetable Crops in the Upcountry Intermediate Zone”. Journal of the National Science Foundation of Sri Lanka, vol. 25, no. 1, 1997, pp. 59–68. DOI: http://doi.org/10.4038/jnsfsr.v25i1.5019