@article{TIMM_2012_18_4_a26,
     author = {A. G. Chentsov},
     title = {Tier mappings and ultrafilter-based transformations},
     journal = {Trudy Instituta matematiki i mehaniki},
     pages = {298--314},
     year = {2012},
     volume = {18},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TIMM_2012_18_4_a26/}
}