@article{1183736305, author = {LeBlanc, Hugues}, title = {Subformula Theorems for $N$-Sequents}, journal = {J. Symbolic Logic}, volume = {33}, number = {1}, year = {1968}, pages = { 161-179}, language = {en}, url = {http://dml.mathdoc.fr/item/1183736305} }
LeBlanc, Hugues. Subformula Theorems for $N$-Sequents. J. Symbolic Logic, Tome 33 (1968) no. 1, pp. 161-179. http://gdmltest.u-ga.fr/item/1183736305/