GUPTA, Lipsy; KUNDU, Subiman. Functions that preserve certain classes of sequences and locally Lipschitz functions. Annales Fennici Mathematici, [S. l.], v. 45, n. 2, p. 699–722, 2020. DOI: 10.5186/aasfm.2020.4542. Disponível em: https://afm.journal.fi/article/view/135878. Acesso em: 13 apr. 2026.