@article{1093635417,
author = {Buss, Samuel R.},
title = {The modal logic of pure provability.},
journal = {Notre Dame J. Formal Logic},
volume = {31},
number = {2},
year = {1990},
pages = { 225-231},
language = {en},
url = {http://dml.mathdoc.fr/item/1093635417}
}
Buss, Samuel R. The modal logic of pure provability.. Notre Dame J. Formal Logic, Tome 31 (1990) no. 2, pp. 225-231. http://gdmltest.u-ga.fr/item/1093635417/