Antropova, L., T. Zalavina, L. Polyakova, and Y. Yuzhakova. “Extralinguistic Conditions of Language Variability in National Languages”. Amazonia Investiga, Vol. 9, no. 25, Jan. 2020, pp. 266-73, https://amazoniainvestiga.info/index.php/amazonia/article/view/887.