ABOU-HADEED, Khaled. Formation of Substituted Benzo[a]heptalenes via Bergman Cyclization of Vicinal Di(ethynyl)-heptalenes. CHIMIA, [S. l.], v. 54, n. 12, p. 763, 2000. DOI: 10.2533/chimia.2000.763. Disponível em: https://www.chimia.ch/chimia/article/view/2000_763. Acesso em: 20 apr. 2024.