Zatsepin, A. F., Yu A. Kuznetsova, M. A. Mashkovtsev, and V. N. Rychkov. 2021. “Research on Interband Optical Transitions in Gd2O3: Er Nanoparticles – Prospective System for Energy Convertors”. Advanced Aspects of Engineering Research Vol. 8, May, 129-36. https://doi.org/10.9734/bpi/aaer/v8/7385D.