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@article{MZM_1981_29_3_a1, author = {V. P. Elizarov}, title = {Equivalent definitions of a perfect system and some of its properties}, journal = {Matemati\v{c}eskie zametki}, pages = {335--350}, publisher = {mathdoc}, volume = {29}, number = {3}, year = {1981}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1981_29_3_a1/} }
V. P. Elizarov. Equivalent definitions of a perfect system and some of its properties. Matematičeskie zametki, Tome 29 (1981) no. 3, pp. 335-350. http://geodesic.mathdoc.fr/item/MZM_1981_29_3_a1/