SMAGOWSKA, Bożena. Ultrasonic Noise Sources in a Work Environment. Archives of Acoustics, [S. l.], v. 38, n. 2, p. 169–176, 2013. Disponível em: http://acoustics.ippt.gov.pl/index.php/aa/article/view/29. Acesso em: 2 jun. 2026.