". . . a very readable book . . . clearly written book can be highly recommended to students with interests in ordinary differential equations. Non-experts and researchers in natural sciences will also find interesting methods that are useful in applications." – In EMS Newsletter, March 2008"Covering an important asymptotic method of differential equations, this book provides a thorough understanding of the method of averaging theory and its resulting applications." – in L’Enseignment Math, 2007