Liudmila Vasilevna Kashirskaya, Alexey Alexandrovich Sitnov, Maiya Anatolevna Azarskaya, Yulia Aleksandrovna Zurnadzhyants. 2020. “Economical and Mathematical Methods for Monitoring Environmentally Significant Business Systems”. International Journal of Advanced Science and Technology 29 (9s), 2241 -53. http://sersc.org/journals/index.php/IJAST/article/view/14562.