PETRENKO, Oleksandr. “CERTIFICATION OF IT COMPANIES’ OWN PERSONNEL AND USERS OF THEIR SOFTWARE”. Herald of Khmelnytskyi National University. Economic sciences 340, no. 2 (March 27, 2025): 501–505. Accessed January 28, 2026. https://heraldes.khmnu.edu.ua/index.php/heraldes/article/view/1721.