@article{03908413,
title = {Positive logic with double negation.},
journal = {Publications de l'Institut Math\'ematique. Nouvelle S\'erie},
volume = {36(50)},
year = {1984},
pages = {21-31},
zbl = {0569.03010},
language = {en},
url = {http://dml.mathdoc.fr/item/03908413}
}
Božić, Milan. Positive logic with double negation.. Publications de l'Institut Mathématique. Nouvelle Série, Tome 36(50) (1984) pp. 21-31. http://gdmltest.u-ga.fr/item/03908413/