@article{1183739304, author = {Goldblatt, R. I.}, title = {First-Order Definability in Modal Logic}, journal = {J. Symbolic Logic}, volume = {40}, number = {1}, year = {1975}, pages = { 35-40}, language = {en}, url = {http://dml.mathdoc.fr/item/1183739304} }
Goldblatt, R. I. First-Order Definability in Modal Logic. J. Symbolic Logic, Tome 40 (1975) no. 1, pp. 35-40. http://gdmltest.u-ga.fr/item/1183739304/