Gandhy, Abel, Harianto, Rita Nurmalina, and Suharno. “The Efficiency of The Spot Market And Crude Palm Oil (CPO) Commodity Futures Market Before and During The Covid-19 Pandemic in Indonesia”. Jurnal Manajemen & Agribisnis 19, no. 1 (March 31, 2022): 139. Accessed January 31, 2023. https://jma.journal.ipb.ac.id/index.php/jmagr/article/view/40165.