Clinical Characteristics of Overseas Imported and Local COVID-19 Cases in Hebei Province 
ZHAO Lei,QIN Hao,DAI Erhei,WANG Yuling,XU Zungui,SHI Xuehan,ZHANG Zhi,YANG Ming,FENG Caixia,XUE Jian
Chinese General Practice . 2020, (35): 4425 -4429 .  DOI: 10.12114/j.issn.1007-9572.2020.00.596