@article{DM_2020_32_1_a0,
     author = {A. A. Voronenko and A. S. Okuneva},
     title = {Universal functions for linear functions depending on two variables},
     journal = {Diskretnaya Matematika},
     pages = {3--7},
     publisher = {mathdoc},
     volume = {32},
     number = {1},
     year = {2020},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_2020_32_1_a0/}
}