[ \nabla^2 \mathbfE = \mu \varepsilon \frac\partial^2 \mathbfE\partial t^2 ]
Estudio de campos eléctricos en el vacío y en presencia de dieléctricos.
Covers static charges in a vacuum, solutions to electrostatic problems (including boundary-value problems), and the behavior of fields in dielectric media .
Fundamentos de la Teoría Electromagnética by Reitz, Milford, and Christy Intent: Locate a digital (PDF) copy of the academic textbook.
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$$\nabla \times B = \mu_0 J + \mu_0 \epsilon_0 \frac\partial E\partial t$$
: Unlike some texts, it places heavy emphasis on the microscopic constitution of matter to better explain fields inside various materials. Practical Tools