Muntianaitė-Dulkinienė, I., V. Poškaitis, A. Vainoras, J. Jurevičius, L. Bikulčienė, and Z. Navickas. “Cointegration of Different ECG Parametres for Various Physical Tasks”. Elektronika Ir Elektrotechnika, vol. 94, no. 6, July 2009, pp. 77-80, https://eejournal.ktu.lt/index.php/elt/article/view/10111.