@article{10_14708_cm_v16i1_5734,
     author = {T. Rumak},
     title = {Some theorems about difference inequalities},
     journal = {Commentationes Mathematicae},
     pages = { 159--164},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {1972},
     doi = {10.14708/cm.v16i1.5734},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/cm.v16i1.5734/}
}