Wan Mohd Zabaria, W. N., N. Abu Hanit, and S. Ahmad. “Mekanisme Mata Wang Dan Kemeruapan Indikator Ekonomi Dunia: Penilaian Semula Ke Atas Piawaian Emas: Currency Mechanism and World Economic Volatility Indicator: Reevaluation of Gold Standard”. The Journal of Muamalat and Islamic Finance Research, vol. 8, no. 1, Jan. 2011, pp. 163-86, https://jmifr.usim.edu.my/index.php/jmifr/article/view/137.