Dobrucky, B., J. Sedo, and R. Konarik. “Combining DVR and UPS Techniques for an Uninterruptable Supply of Ultra-Sensitive Non-Linear Appliances”. Elektronika Ir Elektrotechnika, vol. 26, no. 3, June 2020, pp. 28-35, doi:10.5755/j01.eie.26.3.25769.