[1] https://www.reuters.com/markets/commodities/poland-ukraine-increase-2022-coal-production-weather-cold-months-2022-06-24/
[2] https://www.bloomberg.com/news/articles/2022-06-27/asia-coal-prices-hit-record-on-hot-global-competition-for-fuel
[3] https://www.reuters.com/world/china/power-demand-parts-china-sets-new-records-amid-searing-heat-2022-06-20/
[4] https://www.reuters.com/business/energy/china-cut-coal-import-tariffs-zero-may-1-2022-04-28/
[5] https://www.reuters.com/markets/commodities/quantity-over-quality-china-faces-power-supply-risk-despite-coal-output-surge-2022-06-21/