L. FILIPCZYŃSKI, “Detectability of blood vessels by means of the ultrasonic echo method using a focused ultrasonic beam”, Arch. Acoust., vol. 7, no. 3-4, pp. 253–270, Dec. 1982, Accessed: Mar. 04, 2026. [Online]. Available: https://acoustics.ippt.gov.pl/index.php/aa/article/view/3286