%0 Journal Article %A P. Erdös %A A. Hajnal %T Some remarks on set theory XI %J Fundamenta Mathematicae %D 1973 %P 261-265 %V 81 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/fm-81-3-261-265/ %R 10.4064/fm-81-3-261-265 %G en %F 10_4064_fm_81_3_261_265