1. Agricultural Transformation Agency (ATA). 2019. Soil Fertility Status and Fertilizer Recommendation Atlas for Oromia Regional State. Addis Ababa, Ethiopia.
2. Allen, R. G., Periera, L. S., Raes, D. and Smith, M. 1998. Crop Evapotranspiration (Guidelines for Computing Crop Water Requirements), FAO, Irrigation and Drainage Paper No 56, FAO, Rome, Italy.
3. Andriamananjara, A., T. Rakotoson, T. Razafimbelo, L. Rabeharisoa, M.P. Razafimanantsoa, and D. Masse. 2019. Farmyard manure improves phosphorus use efficiency in weathered P deficient soil. Nutrient Cycling in Agroecosystems 115 (3): 407–425.
4. Ansari, A.A., and S.S. Gill. 2014. Eutrophication: Causes, consequences and control: Volume 2. In Eutrophication: Causes, Consequences and Control: 2: 1–264.
5. Badr, M.A., W.A. El-tohamy, and A.M. Zaghloul. 2012. Yield and water use efficiency of potato grown under different irrigation and nitrogen levels in an arid region. Agricultural Water Management 110: 9–15.