Valda, A. V., and A. P. Levitsky. “Cariesprofilactic and Parodontoprotective Effects of Oral Gel ‘Quertulin’ on Rats, Which Received Prednisolone”. Journal of Education, Health and Sport, vol. 7, no. 2, Feb. 2017, pp. 711-20, https://apcz.umk.pl/JEHS/article/view/5207.