For citations:
Moisejkina L.G., Darda E.S. . Statistics and Economics. 2015;(6):91-94. (In Russ.) https://doi.org/10.21686/2500-3925-2015-6-91-94
Moisejkina L.G., Darda E.S. . Statistics and Economics. 2015;(6):91-94. (In Russ.) https://doi.org/10.21686/2500-3925-2015-6-91-94