1. Abimbola, W. (1964). The ruins of Oyo division. African Notes, 2(1), 16–19.
2. project, Department of Archaeology and Anthropology);MO Adesina,1979
3. Agbaje-Williams, B. (1989). The discovery of Koso, an ancient Oyo settlement. The Nigerian Field, 54, 123–127.
4. Ajayi, J. F. A., & Smith, R. (1971). Yoruba warfare in the nineteenth Century. Ibadan: Ibadan University Press.
5. Aremu, D. A. (1979). Preservation of archaeological resources in Old Oyo National Park: A means of promoting cultural heritage and tourism in the park. Report Submitted to Old Oyo National Park, Nigeria.