@article{PDMA_2012_5_a12,
     author = {M. A. Pudovkina},
     title = {Properties of $X,S$-layers},
     journal = {Prikladnaya Diskretnaya Matematika. Supplement},
     pages = {26--28},
     publisher = {mathdoc},
     number = {5},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PDMA_2012_5_a12/}
}