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http://reply.papertrans.cn/4/304/30321/30321-32.png
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Submitted on: 25 December 2018.
Revised on: 26 January 2019.
Accepted on: 05 February 2019.
Vestnik Sankt-Peterburgskogo Universiteta-Ekonomika-St Petersburg University Journal of Economic Studies
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Submitted on: 29 July 2020.
Revised on: 05 August 2020.
Accepted on: 15 August 2020.
Vestnik Sankt-Peterburgskogo Universiteta-Ekonomika-St Petersburg University Journal of Economic Studies