Tobechukwu, N. M. ., and I. M. . Azubuike. “Panel Data Estimators in the Presence of Serial and Spatial Correlation With Panel Heteroscedasticity: A Simulation Study”. Quarterly Journal of Econometrics Research , vol. 6, no. 1, Oct. 2020, pp. 1-11, doi:10.18488/journal.88.2020.61.1.11.