@article{Liu2020,
author = {Liu, H. and Chen, S. and Liu, M. and Nie, H. and Lu, H.},
title= {Comorbid chronic diseases are strongly correlated with disease severity among COVID-19 patients: A systematic review and meta-analysis},
year = {2020},
doi = {10.14336/AD.2020.0502},
volume = {11},
number = {3},
pages = {668--678},
}