Fadillah Mardianto, M. Fariz, Hanny Valida, Farah Fauziah Putri, Doni Muhammad Fauzi, and Elly Pusporani. “PREDICTION OF THE INDONESIA COMPOSITE INDEX (ICI) USING THE ARCH GARCH APPROACH AND THE FOURIER SERIES”. BAREKENG: Jurnal Ilmu Matematika dan Terapan 20, no. 1 (November 24, 2025): 0271-0286. Accessed November 26, 2025. https://ojs3.unpatti.ac.id/index.php/barekeng/article/view/17973.