Xu C, Xu C. Energy Transition, Environmental Sustainability and Healthcare Costs in Emerging Sub-Saharan Economies: Evidence from the Pre- and During-COVID-19 Periods – Implications for SDG 3, SDG 7 and SDG 13 . PROBL EKOROZW [Internet]. 2026 Jan. 10 [cited 2026 Jan. 14];21(1):173-204. Available from: https://ph.pollub.pl/index.php/preko/article/view/7743