You can find the text and related study materials through the following sources:
– Preview or limited search: https://books.google.com/books?id=oH1PAAAAMAAJ You can find the text and related study
Ian N. Sneddon's "Elements of Partial Differential Equations," widely available through Dover Publications You can find the text and related study
: Examines the physics of vibrating strings and membranes, covering elementary solutions and the Riemann-Volterra method. You can find the text and related study