1. Abaje, I. B., Ati, O. F., Iguisi, E. O., & Jidauna, G. G. (2013). Droughts in the sudano-sahelian ecological zone of Nigeria: implications for agriculture and water resources development. Global Journal of Human Social Science (B): Geography. Geo-Sciences & Environmental, 13(2), 1–10.
2. Abdulrahim, M., Ifabiyi, I., & Ismaila, A. (2013). Time series analyses of mean monthly rainfall for drought management in Sokoto, Nigeria. Ethiopian Journal of Environmental Studies and Management, 6(5). https://doi.org/10.4314/ejesm.v6i5.3.
3. Adeaga, O. (2013). Drought risks and impact on water resources in part of northern Nigeria. IAHS-AISH Proceedings and Reports, 359, 124–129 https://pdfs.semanticscholar.org/717e/90e06f5f6d8301ac0b2f571b4e2b0a3896e9.pdf.
4. Akeh, L. E., Nnoli, N., Gbuyiro, S., Ikehua, F., & Ogunbo, S. (2000). Meteorological Early Warning Systems (EWS) for drought preparedness and drought management in Nigeria. Early Warning Systems for Drought Preparedness and Drought Management, 154.
5. Alley, W. M. (1985). The Palmer Drought Severity Index as a measure of hydrologic. Water Resources Bulletin, 21, 105–114.