E HERAWATI; GULTOM, S. N. R. On Certain Type of Sequence Spaces Defined by 𝝋 − Function . Journal of Research in Mathematics Trends and Technology, [S. l.], v. 1, n. 2, p. 61–67, 2019. DOI: 10.32734/jormtt.v1i2.2838. Disponível em: https://talenta.usu.ac.id/jormtt/article/view/2838. Acesso em: 26 aug. 2025.