%0 Journal Article %A P. Knight %T Algebraic equivalence of ordinal numbers %J Fundamenta Mathematicae %D 1971 %P 235-247 %V 73 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/fm-73-3-235-247/ %R 10.4064/fm-73-3-235-247 %G en %F 10_4064_fm_73_3_235_247