Zulkifli, F. B., Z. B. Mohmed, and N. A. B. Azmee. “Huber M-Estimator for Cumulative Odds Model With Application to the Measurement of Students’ Final Exam Grades”. Pakistan Journal of Statistics and Operation Research, Vol. 18, no. 2, June 2022, pp. 337-4, doi:10.18187/pjsor.v18i2.2996.