TY - JOUR AU - Zheng, Z; Peng, F; Xu, B TI - Risk factors of critical & mortal COVID-19 cases: a systematic literature review and meta-analysis JO - J Infect IS - 02 VL - 81 PY - 2020 DO - 10.1016/j.jinf.2020.04.021 L3 - PubMed-ID: 32335169 SP - e16 EP - e25 ER -