Comparison of alfentanil and fentanyl in painless colonoscopy in children. Medical Research, [S. l.], v. 6, n. 2, p. 1–16, 2024. DOI: 10.6913/mrhk.060201. Disponível em: https://mrhk.cc/index.php/mrhk/article/view/2.. Acesso em: 21 nov. 2024.