MACK, C.; CHURCHILL, L.; ARRABITO, G. Results of a survey on audio and visual warning systems for military helicopters. Canadian Acoustics, [S. l.], v. 26, n. 3, p. 42–43, 1998. Disponível em: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/1148. Acesso em: 28 jan. 2023.