J. Żera and R. Młyński, “Efficiency of attenuating high-level acoustic impulses with double protection (earplugs and earmuffs used simultaneously)”, Arch. Acoust., vol. 31, no. 4(S), pp. 319–324, Jan. 2006, Accessed: Apr. 18, 2026. [Online]. Available: http://acoustics.ippt.gov.pl/index.php/aa/article/view/1362