Shvachko S., Pyshchyk N., and Shumenko О. “Shvachko S., Pyshchyk N., Shumenko О. Categorization Vs Conceptualization (based on Metasign ‘nothing’)”. Philological Treatises, vol. 6, no. 4, Apr. 2020, pp. 69-73, https://tractatus.sumdu.edu.ua/index.php/journal/article/view/387.