Geochemical characteristics and sources of natural gas in the Upper Paleozoic limestone strata, Ordos Basin. - Zhang, Wen; Wang, Qian-Ping; Liu, Wen-Hui; Shi, Ping-Ping; Luo, Hou-Yong; Liu, Peng; Chen, Xiao-Yan; Zhang, Qian; Wang, Xiao-Feng; Zhang, Dong-Dong; Wang, Yi-Ran; Li, Fu-Qi (Petroleum Science (KeAi Communications Co.), 2026)