Marushchak, Yaroslav     Synthesis of automatic control systems by using binomialand Butterworth standard fractional order forms [Текст] / Yaroslav Marushchak, Bohdan Kopchak // Computational problems of electrical engineering / Lviv Polytechnic nat. univ. ; ed.-in-chief Yuriy Bobalo. — Lviv : lviv Polytechnic nat. univ., 2012. — P. 89–94.