LANGLEY, J. K. Linear differential polynomials in zero-free meromorphic functions. Annales Fennici Mathematici, [S. l.], v. 43, n. 2, p. 693–735, 2018. DOI: 10.5186/aasfm.2018.4348. Disponível em: https://afm.journal.fi/article/view/135752. Acesso em: 20 may. 2024.