@article{1093894301, author = {Soboci\'nski, Boles\l aw}, title = {A new class of modal systems.}, journal = {Notre Dame J. Formal Logic}, volume = {12}, number = {1}, year = {1971}, pages = { 371-377}, language = {en}, url = {http://dml.mathdoc.fr/item/1093894301} }
Sobociński, Bolesław. A new class of modal systems.. Notre Dame J. Formal Logic, Tome 12 (1971) no. 1, pp. 371-377. http://gdmltest.u-ga.fr/item/1093894301/