John Corcoran, George Weaver. Logical consequence in modal logic. II. Some semantic systems for S4. Notre Dame Journal of Formal Logic, 15(3):370-378, 1974. [doi]
@article{CorcoranW74,
title = {Logical consequence in modal logic. II. Some semantic systems for S4},
author = {John Corcoran and George Weaver},
year = {1974},
doi = {10.1305/ndjfl/1093891400},
url = {http://dx.doi.org/10.1305/ndjfl/1093891400},
researchr = {https://researchr.org/publication/CorcoranW74},
cites = {0},
citedby = {0},
journal = {Notre Dame Journal of Formal Logic},
volume = {15},
number = {3},
pages = {370-378},
}