Dobrovolsky , Yu., H. Prokhorov, L. Diachenko, W. Zukow, V. Babelyuk, and I. Popovych. 2022. “Correlation Investigation of the Brightness of GDE-Grams Using the Methods of Computer Graphics and Direct Measurements”. Journal of Education, Health and Sport 12 (7):366-72. https://doi.org/10.12775/JEHS.2022.12.07.035.