On Interrelation of Such Concepts as «Variant», «Invariant», «Variativity» in Slavic Language Study. Philological Studies: Scientific Bulletin of Kryvyi Rih State Pedagogical University, [S. l.], v. 9, n. 2, p. 181–185, 2013. DOI: 10.31812/filstd.v9i2.471. Disponível em: https://journal.kdpu.edu.ua/filstd/article/view/471. Acesso em: 5 dec. 2025.