@article{1183731708, author = {Simons, Leo}, title = {New Axiomatizations of S3 and S4}, journal = {J. Symbolic Logic}, volume = {18}, number = {1}, year = {1953}, pages = { 309-316}, language = {en}, url = {http://dml.mathdoc.fr/item/1183731708} }
Simons, Leo. New Axiomatizations of S3 and S4. J. Symbolic Logic, Tome 18 (1953) no. 1, pp. 309-316. http://gdmltest.u-ga.fr/item/1183731708/