The book "Asymptotic decompositions of solutions of singularly perturbed equations" by the authors Vasilyev A. B. and Butuzova V. F. represents an important contribution to the field of mathematical analysis and the theory of differential equations. This publication will be particularly interesting to those engaged in scientific research in the field of applied mathematics, physics and engineering, as well as students and graduate students seeking to deepen their knowledge in this complex but fascinating topic. The book focuses on singularly perturbed equations that arise in various fields of science and technology. These equations are mathematical models in which there are small parameters that affect the behavior of decisions. The authors examine in detail the methods of asymptotic decomposition, allowing readers to understand how approximate solutions of such equations can be found. This knowledge can be applied in a variety of fields from mechanics to biology, from financial models to ecology. The book is written in accessible language, which makes it suitable not only for professionals, but also for students who are just beginning to get acquainted with this topic. Authors, Vasiliev A. B. and Butuzov V. F. are recognized specialists in the field of mathematical modeling and the theory of differential equations, which gives additional value to their work Their experience and deep knowledge allow them not only to explain complex concepts, but also to do it in a fascinating and understandable form. The topics raised in the book cover a wide range of issues related to asymptotic analysis. Readers will be able to learn about various methods, such as the regular and singular. method. Perturbation, as well as the application of these methods to specific tasks. The authors share their findings and research results, which makes the book not only a theoretical guide, but also a practical guide. The book will be especially useful for those who are interested in mathematical modeling and its application in real-world problems. It can become a reference book for students of mathematical and engineering specialties, as well as for researchers working in the field of applied mathematics. Due to its content and style of presentation, “Asymptotic decompositions of solutions of singularly perturbed equations” will attract the attention of both beginners and experienced specialists. If you are looking for literature that will help you better understand asymptotic methods and their application in solving singularly perturbed equations, then this book will be a real find for you. It will not only expand your knowledge, but also inspire new research and discoveries in mathematics and its applications. In addition, it is worth noting that the authors actively publish their work in scientific journals and participate in conferences, which indicates their high level of professionalism and relevance of the topics studied. The book “Asymptotic decompositions of solutions of singularly perturbed equations” is not just a textbook, but a real encyclopedia of knowledge for those who strive for new heights in mathematics and its applications. Do not miss the opportunity to immerse yourself in the world of asymptotic analysis and discover new horizons in the study of singularly perturbed equations. This book will be your reliable companion on the way to understanding complex mathematical concepts and their practical application.