Kutsevlyak, V. F., V. V. Grischenko, and J. V. Nikitchenko. 2008. “Experimental Investigation of Animals Prooxidant-Antioxidant Balance During the Induced Generalized Periodontitis and Its Correction by Cryopreserved Human Placenta Extract”. Problems of Cryobiology and Cryomedicine 18 (4):482-85. https://journal.cryo.org.ua/index.php/probl-cryobiol-cryomed/article/view/357.