@article{1094068851, author = {Cresswell, M. J.}, title = {Alternative completeness theorems for modal systems.}, journal = {Notre Dame J. Formal Logic}, volume = {8}, number = {3}, year = {1967}, pages = { 339-345}, language = {en}, url = {http://dml.mathdoc.fr/item/1094068851} }
Cresswell, M. J. Alternative completeness theorems for modal systems.. Notre Dame J. Formal Logic, Tome 8 (1967) no. 3, pp. 339-345. http://gdmltest.u-ga.fr/item/1094068851/