@article{1183740835,
author = {Girard, Jean-Yves and Pappinghaus, Peter},
title = {A Result on Implications of $\Sigma\_1$-Sentences and Its Application to Normal Form Theorems},
journal = {J. Symbolic Logic},
volume = {46},
number = {1},
year = {1981},
pages = { 634-642},
language = {en},
url = {http://dml.mathdoc.fr/item/1183740835}
}
Girard, Jean-Yves; Pappinghaus, Peter. A Result on Implications of $\Sigma_1$-Sentences and Its Application to Normal Form Theorems. J. Symbolic Logic, Tome 46 (1981) no. 1, pp. 634-642. http://gdmltest.u-ga.fr/item/1183740835/