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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cheb</journal-id><journal-title-group><journal-title xml:lang="ru">Чебышевский сборник</journal-title><trans-title-group xml:lang="en"><trans-title>Chebyshevskii Sbornik</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-8383</issn><publisher><publisher-name>Tula State Lev Tolstoy  Pedagogical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22405/2226-8383-2019-20-2-348-365</article-id><article-id custom-type="elpub" pub-id-type="custom">cheb-618</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Статьи</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Article</subject></subj-group></article-categories><title-group><article-title>О неравенствах типа Колмогорова для периодических функций двух переменных в L2</article-title><trans-title-group xml:lang="en"><trans-title>About Kolmogorov type of inequalities for periodic functions of two variables in L2</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шабозов</surname><given-names>Мирганд Шабозович</given-names></name><name name-style="western" xml:lang="en"><surname>Shabozov</surname><given-names>Mirgand Shabozovich</given-names></name></name-alternatives><email xlink:type="simple">shabozov@mail.ru</email></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Акобиршоев</surname><given-names>Мухиддин Отамшоевич</given-names></name><name name-style="western" xml:lang="en"><surname>Akobirshoev</surname><given-names>Mukhiddin Otasevic</given-names></name></name-alternatives></contrib></contrib-group><pub-date pub-type="collection"><year>2019</year></pub-date><pub-date pub-type="epub"><day>23</day><month>01</month><year>2020</year></pub-date><volume>20</volume><issue>2</issue><fpage>348</fpage><lpage>365</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Шабозов М.Ш., Акобиршоев М.О., 2019</copyright-statement><copyright-year>2019</copyright-year><copyright-holder xml:lang="ru">Шабозов М.Ш., Акобиршоев М.О.</copyright-holder><copyright-holder xml:lang="en">Shabozov M.S., Akobirshoev M.O.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.chebsbornik.ru/jour/article/view/618">https://www.chebsbornik.ru/jour/article/view/618</self-uri><abstract/><trans-abstract xml:lang="en"><p>.</p></trans-abstract></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Колмогоров А. 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