@article{1093894157,
author = {Gass, Frederick S.},
title = {Generalized ordinal notation.},
journal = {Notre Dame J. Formal Logic},
volume = {12},
number = {1},
year = {1971},
pages = { 104-114},
language = {en},
url = {http://dml.mathdoc.fr/item/1093894157}
}
Gass, Frederick S. Generalized ordinal notation.. Notre Dame J. Formal Logic, Tome 12 (1971) no. 1, pp. 104-114. http://gdmltest.u-ga.fr/item/1093894157/