Mel'nik, T. A. “Decomposition of Systems of Quasidifferential Equations With Rapid and Slow Variables”. Ukrains’kyi Matematychnyi Zhurnal 51, no. 3 (March 25, 1999): 413–417. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4625.