Kupchishin, A.I., and K.B. Tlebaev. “‘X-RAY STRUCTURAL STUDIES OF POLYETHETRAFLUOROETHYLEN ’”. Eurasian Physical Technical Journal, vol. 15, no. 1(29), Mar. 2018, pp. 29-33, https://phtj.buketov.edu.kz/EPTJ/article/view/499.