Savenko, O. S., S. M. Lysenko, and A. O. Nicheporuk. 2015. “Models of Levels of Polymorphic Viruses”. Visnyk of Vinnytsia Politechnical Institute, no. 2 (March):75-83. https://visnyk.vntu.edu.ua/index.php/visnyk/article/view/814.