Investigation of Changes in the Absorption Spectrum of Modern Chlorine-Containing Medicines for Photodynamic Therapy and Methylene Blue as a Result of Exposure to LED Emissions with a wavelength of 656 ± 10 nm. - Belikov, A. V.; Semyashkina, Yu. V.; Smirnov, S. N.; Tavalinskaya, A. D. (Optics & Spectroscopy, 2020)