Romaškevičius, O., M. Šiožinys, and J. A. Virbalis. “The Influence of Exciting Current Unbalance to Parameters of Rotating Magnetic Field”. Elektronika Ir Elektrotechnika, vol. 83, no. 3, Mar. 2008, pp. 85-88, https://eejournal.ktu.lt/index.php/elt/article/view/11084.