“The Enrichment Conditions and Resource Potential of Marine-Continental Transitional Coal-Measure Shale Gas: A Case Study of the Permo-Carboniferous Systerm in the Huanghebei Coalfield of North China”. Global Journal of Earth Science and Engineering, vol. 7, no. 1, Oct. 2020, pp. 22-36, https://doi.org/10.15377/2409-5710.2020.07.2.