The 3 references without contexts in paper N. Epshtein A., Н. Эпштейн А. (2018) “О допустимых значениях порога игнорирования примесей и отношения сигнал/шум при проверке чувствительности хроматографической системы // On acceptable values of disregard limits for impurities and signal-to-noise ratio when checking chromatographic system sensitivity” / spz:neicon:vedomostincesmp:y:2017:i:2:p:85-91

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Epshtein NA. Validation of HPLC Techniques for Pharmaceutical Analysis. Pharmaceutical Chemistry Journal 2004; 38(4): 40–56 (in Russian).
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Beregovykh VV, ed. Validation of analytical procedures for drug manufacturers. Guiding principles for drug manufacturers. Moscow: Litterra; 2008 (in Russian).
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Commentary USP 39 — NF 34. US Pharmacopeial Convention. November 2, 2015. Available from: https:// goo.gl/wPovtY.
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