@article{1093890892, author = {Collier, Kenneth W.}, title = {Physical modalities and the system $E$.}, journal = {Notre Dame J. Formal Logic}, volume = {14}, number = {1}, year = {1973}, pages = { 185-194}, language = {en}, url = {http://dml.mathdoc.fr/item/1093890892} }
Collier, Kenneth W. Physical modalities and the system $E$.. Notre Dame J. Formal Logic, Tome 14 (1973) no. 1, pp. 185-194. http://gdmltest.u-ga.fr/item/1093890892/