@article{PDMA_2012_5_a10,
     author = {B. A. Pogorelov and M. A. Pudovkina},
     title = {On combinatorial properties of the group generated by $XL$ layers},
     journal = {Prikladnaya Diskretnaya Matematika. Supplement},
     pages = {22--23},
     year = {2012},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PDMA_2012_5_a10/}
}