@article{MASLO_1972_22_4_a5,
     author = {\v{S}al\'at, Tibor},
     title = {On {Certain} {Classes} of {Sets} of {Natural} {Numbers}},
     journal = {Mathematica slovaca},
     pages = {291--296},
     year = {1972},
     volume = {22},
     number = {4},
     mrnumber = {0313215},
     zbl = {0249.10050},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MASLO_1972_22_4_a5/}
}