@article{1183730734,
author = {Fitch, Frederic B.},
title = {A Further Consistent Extension of Basic Logic},
journal = {J. Symbolic Logic},
volume = {14},
number = {4},
year = {1950},
pages = { 209-218},
language = {en},
url = {http://dml.mathdoc.fr/item/1183730734}
}
Fitch, Frederic B. A Further Consistent Extension of Basic Logic. J. Symbolic Logic, Tome 14 (1950) no. 4, pp. 209-218. http://gdmltest.u-ga.fr/item/1183730734/