InhaltsangabePreface to the Second Russian Edition.- 1. The General Theory to one First-Order Equation.- 2. The General Theory to one First-Order Equation (Continued).- 3. Huygens' Principle in the Theory of Wave Propagation.- 4. The Vibrating String (d'Alembert's Method).- 5. The Fourier Method (for the Vibrating String).- 6. The Theory of Oscillations. The Variational Principle.- 7. The Theory of Oscillations. The Variational Principle (Continued).- 8. Properties of Harmonic Functions.- 9. The Fundamental Solution for the Laplacian. Potentials.- 10. The Double Layer Potential.- 11. Spherical Functions. Maxwell's Theorem. The Removable Singularities Theorem.- 12. Boundary Value Problems for Laplace's Equation. Theory of Linear Equations and Systems.- A. The Topological Content of Maxwell's Theorem on the Multifield Representation of Spherical Functions.- B. Problems.