M. AXINTE, M.-C. PERJU, C. NEJNERU, I. HOPULELE, and I. CIMPOEŞU, “Quality Surface Analysis for Polarized Grid Plasma Nitridings”, The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science, vol. 36, no. 1, pp. 51-56, Mar. 2013.