1. Yu. S. Boyarskaya, Crystal Deformation under Microhardness Testing (Shtiintsa, Kishinev, 1972) [in Russian].
2. M. A. Velednitskaya, V. N. Roshanskii, L. F. Comolova, G. V. Saparin, J. Schreiber, and O. Brummer, Phys. Status Solidi A 32, 123 (1975).
3. V. K. Grigorovich, Hardness and Microhardness of Metals (Nauka, Moscow, 1976) [in Russian].
4. Yu. S. Boyarskaya, D. Z. Grabco, and M. S. Kats, Physics of Microindentation Processes (Shtiintsa, Kishinev, 1986) [in Russian].
5. V. Domnich and Y. Gogotsi, Rev. Adv. Mater. Sci. 3, 1 (2002).