A multicenter study of the birth condition of preterm infants and the causes of preterm birth in Henan Province, China
LIU Ya-Xuan, XU Fa-Lin, DUAN Wen-Li, DONG Hui-Fang, WANG Yin-Juan, ZHANG Yi, ZHANG Ru
CJCP . 2021, (2): 121 -126 .  DOI: 10.7499/j.issn.1008-8830.2010063