@article{1093894011, author = {Soboci\'nski, Boles\l aw}, title = {Note on Zeman's modal system $S4.04$.}, journal = {Notre Dame J. Formal Logic}, volume = {11}, number = {1}, year = {1970}, pages = { 383-384}, language = {en}, url = {http://dml.mathdoc.fr/item/1093894011} }
Sobociński, Bolesław. Note on Zeman's modal system $S4.04$.. Notre Dame J. Formal Logic, Tome 11 (1970) no. 1, pp. 383-384. http://gdmltest.u-ga.fr/item/1093894011/