Ruiz-Vanoye, . J. A., Díaz-Parra, O., Trejo-Macotela, F. R. . and Ramos-Fernández, J. C. . (2020) “Editorial: P versus NP problem from Formal Languages Theory View”, International Journal of Combinatorial Optimization Problems and Informatics, 12(1), pp. 1–8. doi: 10.61467/2007.1558.2021.v12i1.207.