POWAŁOWSKI, Tadeusz. “A Noninvasive Ultrasonic Method for Vascular Input Impedance Determination Applied in Diagnosis of the Carotid Arteries”. Archives of Acoustics, vol. 14, no. 3-4, July 2015, pp. 293-12, https://acoustics.ippt.pan.pl/index.php/aa/article/view/3057.