1. Arndt, P., Mariano, H.L., Pinto, D.C.: Finitary Filter Pairs and Propositional Logics. South American Journal of Logic 4(2), 257–280 (2018)
2. Arndt, P., Mariano, H. L., Pinto, D. C.: Congruence filter pairs, adjoints and Leibniz hierarchy, arXiv:2109.01065, (2021)
3. Arndt, P., Mariano, H. L., Pinto, D. C.: Congruence filter pairs, equational filter pairs and generalizations, in preparation, (2021)
4. Arndt, P., Mariano, H. L., Pinto, D. C.: Horn filter pairs and Craig interpolation in propositional logic, in preparation, (2021)
5. Adámek, J., Rosický, J.: Locally Presentable and Accessible Categories. Lecture Notes Series of the LMS, vol. 189. Cambridge University Press, Cambridge, Great Britain (1994)