Smidtaite, R., Z. Navickas, and E. Venskaityte. “ECG Research Using Elements of Matrix Analysis and Phase Planes”. Elektronika ir Elektrotechnika 103, no. 7 (August 24, 2010): 83–86. Accessed March 25, 2026. https://eejournal.ktu.lt/index.php/elt/article/view/9281.