Medrano Meneses, Mitzunory Enrique, Zeus Salvador Hernández Veleros, and Miguel Angel Torres González. 2023. “How to Determine Whether the Covid-19 Infection Series Are Stationary and Can Be Predicted or Whether They Are Non-Stationary and Cannot Be Predicted?”. International Journal of Combinatorial Optimization Problems and Informatics 14 (2):67-76. https://ijcopi.org/ojs/article/view/352.