HA, TRAN THI HOANG, and PHAM TUAN ANH. 2021. “Management Strategy for Business Sustainability Under Macro Effects In An Econometric Model – Case of PKN Orlens in Oil and Gas Industry in Poland”. The Journal of Contemporary Issues in Business and Government 27 (2):967-71. https://cibgp.com/au/index.php/1323-6903/article/view/1005.