BOR, H. Factors for |n,pn|k summability of infinite series. Annales Fennici Mathematici, [S. l.], v. 16, n. 1, p. 151–154, 1991. DOI: 10.5186/aasfm.1991.1605. Disponível em: https://afm.journal.fi/article/view/134710. Acesso em: 14 apr. 2025.