1. G. G. Gnesin, “Materials science—megascience,” Visn. NAN Ukrainy, No. 1, 73–78 (2012).
2. A. P. Pogozheva, Tripoli Antropomorphic Plastic [in Russian], Nauka, Novosibirsk (1981), p. 137.
3. M. E. Mathieu, Art of Ancient Egypt [in Russian], Iskusstvo, Leningrad–Moscow (1961), p. 591.
4. Ch. Loukotka, Writing Development [Russian translation], Izd. Inostr. Lit., Moscow (1950), p. 320.
5. A. I. Voshchinina, Antique Art [in Russian], Izd. Akad. Khudozh., Moscow (1962), p. 395.