## Bohdan Zabavsky |
## Vasyl’ Petrychkovych |
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Professor Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: zabavskii at gmail.com |
Professor Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: vpetrych at iapmm.lviv.ua |
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## Andriy Gatalevych |
## Volodymyr Shchedryk |
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Associate Professor Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: gatalevych at ukr.net |
Research fellow Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: shchedrykv at ukr.net |
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## Volodymyr Zelisko |
## Nataliia Dzhaliuk |
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Associate Professor Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: zelisko_vol at yahoo.com |
Associate Professor Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: nataliya.dzhalyuk at gmail.com |
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## Yurii Ishchuk |
## Andrij Romaniv |
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Associate Professor Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: yu.ishchuk at gmail.com |
PhD Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: romaniv_a at ukr.net |
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## Ivanna Melnyk |
## Nataliya Ladzoryshyn |
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Associate Professor Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: ivannamelnyk at yahoo.com |
MSc Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: natalja.ladzoryshyn at gmail.com |
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## Marta Maloid-Glebova |
## Bogdan Shavarovskii |
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Teaching assistant Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: martamaloid at gmail.com |
Research fellow Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: bshavarovskii at gmail.com |
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## Vasyl’ Fedorchuk |
## Volodymyr Fedorchuk |
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Extraordinary Professor, Institute of Mathematics, Pedagogical University of Kraków, Poland; Research fellow, Department of Algebra Pidstryhach IAPMM of NAS of Ukraine e-mail: vasfed at gmail.com |
PhD Department of Algebra Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine e-mail: volfed at gmail.com |
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## Andriy Sagan |
## Vasylyna Bokhonko |
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PhD student Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: andrij.sagan at gmail.com |
PhD student Department of Algebra and Logic Faculty of Mechanics and Mathematics Ivan Franko National University of Lviv e-mail: linabokhonko at gmail.com |
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