SCHWARTZBACH, M. I. A note on opaque types. DAIMI Report Series, [S. l.], v. 19, n. 313, 1990. DOI: 10.7146/dpb.v19i313.6703. Disponível em: https://tidsskrift.dk/daimipb/article/view/6703. Acesso em: 6 may. 2024.