@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/