Feng F. The Effects of Tianjin’s Openness on Economic Development in Beijing-Tianjin-Hebei Region Based on Extended Solow Model. IJEFI [Internet]. 2016 Jul. 23 [cited 2024 Nov. 14];6(3):1151-4. Available from: https://econjournals.com./index.php/ijefi/article/view/2389