Pilyugin, Sergei Yu. Introduction to structurally stable systems of differential equations / Sergei Yu. Pilyugin. - Basel : Birkh�auser Verlag, 1992. - ix, 188 p. : ill. ; 24 cm. Includes index. Includes bibliographical references . ISBN: 3764325747 (hbk.) Subjects--Topical Terms: Differential equations.Stability.