Elhia, M., Balatif, O., Boujallal, L. and Rachik, M. 2021. Optimal control problem for a tuberculosis model with multiple infectious compartments and time delays. An International Journal of Optimization and Control: Theories & Applications (IJOCTA). 11, 1 (Jan. 2021), 75–91. DOI:https://doi.org/10.11121/ijocta.01.2021.00885.