STEFFEN, B.; JAY, C. B.; MENDLER, M. Compositional Characterization of Observable Program Properties. DAIMI Report Series, [S. l.], v. 19, n. 328, 1990. DOI: 10.7146/dpb.v19i328.6718. Disponível em: https://tidsskrift.dk/daimipb/article/view/6718. Acesso em: 9 may. 2024.