A. . Nábrádi, K. . Pető, V. . Balogh, . E. . Szabó, A. . Bartha, and . K. . Kovács, “Efficiency indicators in different dimension”, APSTRACT, vol. 3, no. 1-2, pp. 7–22, May 2009, doi: 10.19041/APSTRACT/2009/1-2/1.