@article{10_4064_ap_27_3_265_277,
     author = {Zdzis{\l}aw Denkowski},
     title = {On the existence and uniqueness of periodic solutions for difference equations of second order},
     journal = {Annales Polonici Mathematici},
     pages = {265--277},
     publisher = {mathdoc},
     volume = {27},
     number = {3},
     year = {1972},
     doi = {10.4064/ap-27-3-265-277},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-27-3-265-277/}
}