%0 Journal Article %A W. Żelazko %T On a problem concerning joint approximate point spectra %J Studia Mathematica %D 1973 %P 239-240 %V 45 %N 3 %U http://geodesic.mathdoc.fr/articles/10.4064/sm-45-3-239-240/ %R 10.4064/sm-45-3-239-240 %G en %F 10_4064_sm_45_3_239_240