LOU, Y. Y. Hamman’s syndrome: spontaneous pneumomediastinum and subcutaneous emphysema during second stage of labour. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, [S. l.], v. 6, n. 6, p. 2622–2624, 2017. DOI: 10.18203/2320-1770.ijrcog20172365. Disponível em: https://www.ijrcog.org/index.php/ijrcog/article/view/2751. Acesso em: 4 oct. 2025.