This book is about Lie group analysis of differential equations for physical and engineering problems. The topics include:
-- Approximate symmetry in nonlinear physical problems
-- Complex methods for Lie symmetry analysis
-- Lie group classication, Symmetry analysis, and conservation laws
-- Conservative difference schemes
-- Hamiltonian structure and conservation laws of three-dimensional linear elasticity
-- Involutive systems of partial differential equations
This collection of works is written in memory of Professor Nail H. Ibragimov (1939-2018). It could be used as a reference book in differential equations in mathematics, mechanical, and electrical engineering.