Chukwudi, F. T. (2014). Oral Interview Granted 29th February at Obigwe-Ogba Land. Occupation: Hunter, Age: 71 Years.
 Edmund, U. T. (2010). Theocentric Vision of African Traditional Religion. Lagos: Orange Books.
 Egerson, J. T. (2013). Religion and Traditional Institutions in Africa. London: Green-Wood Publishers.
 Ejor, V. I. (2009). The African Traditional Religion of the Yorubas. Ibadan: Fyne Publishers.
 Eke, W. S. (2014). Oral Interview Granted 15th January 2014 at Omoku-Ogba Land. Occupation: Priest of Earth Deity, Age: 82 Years.
 Idowu, E. B. (1962). Olodamare God in Yoruba Belief. London: Longman.
 Ifeanyi, G. R. (2014). Oral Interview Granted 13th December 2013 at Okposi-Ogba Land. Occupation: Hunter, Age: 74 Years.
 Ikechukwu, C. E. (2014). Oral Interview Granted 27th March 2014 at Obagi-Ogba Land. Occupation: Trader, Age: 69 Years.
 Iwe, N. S. S. (1979). Christianity, Culture and Colonialism in Africa. Port Harcourt: College of Education.
 Kalu, O. U. (1978). Precarious Visions: The African Perceptions of His World. In O. U. Kalu (Ed.), Readings in African Humanities. Enugu: Fourth Dimension Publishers.
 Masi, I. W. (2011). Themes in the Socio-Ethical Values of African Religion. Port Harcourt: View Publishing Company.
 Ogidi, R. B. (2014). Oral Interview Granted 5th March 2014 at Omoku-Ogba Land. Occupation: Farmer, Age: 72 Years.
 Okwu, V. N. (2014). Oral Interview Granted 21st January 2014 at Obosi-Ogba Land. Occupation: Wood Caver, Age: 70 Years.
 Peil, M. (1977). Consensus and Conflict in African Societies. London: Longman.
 Peters, F. U. (2013). Religion and Ethno-Philosophy of Change. Oxford: Clarendon Press.