%0 Journal Article %A J. MikusiƄski %T An approximation theorem and its applications in operational calculus %J Studia Mathematica %D 1966 %P 141-145 %V 27 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-27-2-141-145/ %R 10.4064/sm-27-2-141-145 %G en %F 10_4064_sm_27_2_141_145