Melvin Fitting. Model Existence Theorems for Modal and Intuitionistic Logics. Journal of Symbolic Logic, 38(4):613-627, 1973.
@article{Fitting73, title = {Model Existence Theorems for Modal and Intuitionistic Logics}, author = {Melvin Fitting}, year = {1973}, tags = {modal logic, logic}, researchr = {https://researchr.org/publication/Fitting73}, cites = {0}, citedby = {0}, journal = {Journal of Symbolic Logic}, volume = {38}, number = {4}, pages = {613-627}, }