M. A. Zaitri, M. O. Bibi and D. F. M. Torres, Optimal Control to Limit the Spread of COVID-19 in Italy,
Kuwait Journal of Science, Special Issue on COVID (2021), 1--14.
A. Din, A. Khan, A. Zeb, M. R. Sidi Ammi, M. Tilioua and D. F. M. Torres, Hybrid method for simulation of a fractional COVID-19 model with real case application,
Axioms 10 (2021), no. 4, Art. 290, 17 pp.
S. Vaz and D. F. M. Torres, A Discrete-Time Compartmental Epidemiological Model for COVID-19 with a
Case Study for Portugal, Axioms 10 (2021), no. 4, Art. 314, 14 pp.
Z. Abreu, G. Cantin and C. J. Silva, Analysis of a COVID-19 compartmental model: a mathematical and computational approach,
Math. Biosci. Eng. 18 (2021), no. 6, 7979--7998.
Silvério Rosa and Delfim F. M. Torres, Fractional Modelling and Optimal Control of COVID-19 Transmission in Portugal,
Axioms 11 (2022), no. 4, Art. 170, 15 pp.
P. Agarwal, J. J. Nieto, M. Ruzhansky and D. F. M. Torres, Analysis of Infectious Disease Problems (Covid-19) and Their Global Impact,
Springer Nature, Singapore, 2021