J. U. Okeke, J. C. Nwabueze, and E. N. Okeke, “Individual Effects on First Order Autoregressive Panel Data Model”, IJSBAR, vol. 19, no. 1, pp. 279–284, Jan. 2015, Accessed: Sep. 14, 2025. [Online]. Available: https://gssrr.org/JournalOfBasicAndApplied/article/view/1773