Yang, Tzu-Yi, Thieu Thi Thanh Ha, and Chia-Wei Yen. “Oil Threshold Value Between Oil Price and Production”. Panoeconomicus 66, no. 4 (March 25, 2018): 487–505. Accessed May 2, 2024. http://www.panoeconomicus.org/index.php/jorunal/article/view/409.