UYGUN, S. Notes on Pell and Pell-Lucas Sequences with Negative Subcripts. The Mindanawan Journal of Mathematics, [S. l.], v. 6, n. 1, p. 1–9, 2024. Disponível em: https://journals.msuiit.edu.ph/tmjm/article/view/404. Acesso em: 20 sep. 2024.