%0 Journal Article %A Zdzisław Denkowski %T On the existence and uniqueness of periodic solutions for difference equations of second order %J Annales Polonici Mathematici %D 1972 %P 265-277 %V 27 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/ap-27-3-265-277/ %R 10.4064/ap-27-3-265-277 %G en %F 10_4064_ap_27_3_265_277