1. Electromagnetic Radiation. Chemistry LibreTextshttps://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Fundamentals_of_Spectroscopy/Electromagnetic_Radiation
2. Ionization in the field of a strong electromagnetic wave;Keldysh;Sov. Phys. JETP,1965
3. Electromagnetic Wave Propagation, Radiation, and Scattering: From Fundamentals to Applications;Ishimaru,2017
4. On the guided propagation of electromagnetic wave beams