Aako, O. L., Adewara, J. A., Adekeye, K. S., & Nkemnole, E. B. (2020). X̅ and R control charts based on marshall-olkin inverse log-logistic distribution for positive skewed data. African Journal of Pure and Applied Sciences, 1(1), 9–16. https://doi.org/10.33886/ajpas.v1i1.167