S. A. M. Aris, N. A. Bani, M. N.Muhtazaruddin, and M. N. Taib, “EEG Calmness Index Establishment Using Computational of Z-Score”, IJET, vol. 7, no. 4.11, pp. 44–48, Oct. 2018, doi: 10.14419/ijet.v7i4.11.20686.