Ngosi, Reuben Kyalo, and Jane Omwenga. “Factors Contributing to Non-Productive Time in Geothermal Drilling in Kenya: A Case of Menengai Geothermal Project”. American Scientific Research Journal for Engineering, Technology, and Sciences 14, no. 3 (November 20, 2015): 16–26. Accessed September 17, 2025. https://www.asrjetsjournal.org/American_Scientific_Journal/article/view/1092.