Gorus, Sehid, and Rolf Groeneveld. “Vietnam’s Development Trajectory: Threshold Cointegration and Causality Analysis of Energy Consumption and Economic Growth”. Journal of Energy and Environmental Policy Options , vol. 1, no. 2, June 2018, pp. 28-35, https://resdojournals.com/index.php/JEEPO/article/view/15.