@article{1093882663, author = {Williamson, John}, title = {${\rm S}5$ without modal axioms.}, journal = {Notre Dame J. Formal Logic}, volume = {20}, number = {1}, year = {1979}, pages = { 593-594}, language = {en}, url = {http://dml.mathdoc.fr/item/1093882663} }
Williamson, John. ${\rm S}5$ without modal axioms.. Notre Dame J. Formal Logic, Tome 20 (1979) no. 1, pp. 593-594. http://gdmltest.u-ga.fr/item/1093882663/