HA, TRAN THI HOANG, and PHAM TUAN ANH. “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, no. 2 (April 30, 2021): 967–971. Accessed July 12, 2025. https://www.cibgp.com/index.php/1323-6903/article/view/1005.