Timon, V. V., T. F. Petrenko, and E. I. Goncharuk. “Cryopreservation of Human Fetal Fibroblast Culture”. Problems of Cryobiology and Cryomedicine, vol. 17, no. 1, Mar. 2007, pp. 80-85, https://journal.cryo.org.ua/index.php/probl-cryobiol-cryomed/article/view/535.