@article{1183741706,
author = {Schroeder-Heister, Peter},
title = {A Natural Extension of Natural Deduction},
journal = {J. Symbolic Logic},
volume = {49},
number = {1},
year = {1984},
pages = { 1284-1300},
language = {en},
url = {http://dml.mathdoc.fr/item/1183741706}
}
Schroeder-Heister, Peter. A Natural Extension of Natural Deduction. J. Symbolic Logic, Tome 49 (1984) no. 1, pp. 1284-1300. http://gdmltest.u-ga.fr/item/1183741706/