The effect of passive smoking on respiratory symptoms and pulmonary function in children in Braga. Portuguese Journal of Family Medicine and General Practice, [S. l.], v. 23, n. 6, p. 673–84, 2007. DOI: 10.32385/rpmgf.v23i6.10423. Disponível em: https://rpmgf.pt/ojs/index.php/rpmgf/article/view/10423. Acesso em: 17 apr. 2026.