Chetviorkin, I.I. “Extraction and Use of Opinion Words for the Three-Way Review Classification Problem”. Numerical Methods and Programming (Vychislitel’nye Metody i Programmirovanie) 12, no. 30 (November 10, 2011): 73–81. Accessed December 13, 2025. https://en.num-meth.ru/index.php/journal/article/view/488.