SKYUM, Sven. Parallel Context-Free Languages. DAIMI Report Series, [S. l.], v. 3, n. 30, 1974. DOI: 10.7146/dpb.v3i30.6449. Disponível em: https://tidsskrift.dk/daimipb/article/view/6449. Acesso em: 5 feb. 2026.