@article{1093870574,
author = {\=Ohama, Shigeo},
title = {Conjunctive normal forms and weak modal logics without the axiom of necessity.},
journal = {Notre Dame J. Formal Logic},
volume = {25},
number = {1},
year = {1984},
pages = { 141-151},
language = {en},
url = {http://dml.mathdoc.fr/item/1093870574}
}
Ōhama, Shigeo. Conjunctive normal forms and weak modal logics without the axiom of necessity.. Notre Dame J. Formal Logic, Tome 25 (1984) no. 1, pp. 141-151. http://gdmltest.u-ga.fr/item/1093870574/