SARANEN, J. On decomposition of solutions of some higher order elliptic equations. Annales Fennici Mathematici, [S. l.], v. 4, n. 2, p. 267–277, 1979. DOI: 10.5186/aasfm.1978-79.0423. Disponível em: https://afm.journal.fi/article/view/134353. Acesso em: 25 nov. 2024.