CROSS, R. The essential state diagram of a linear operator. Annales Fennici Mathematici, [S. l.], v. 15, n. 2, p. 283–291, 1990. DOI: 10.5186/aasfm.1990.1506. Disponível em: https://afm.journal.fi/article/view/134692. Acesso em: 25 nov. 2024.