@article{article, title  = {{Vitamin D insufficiency in COVID-19 and influenza A, and critical illness survivors : a cross-sectional study}},

 publisher = {{BMJ Publishing Group}},

 url = {{}},

 year = {{2021}},

 month = {{10}},

 author = {{Hurst EA and Mellanby RJ and Handel I and Griffith DM and Rossi AG and Walsh TS and Shankar-Hari M and Dunning J and Homer NZ and Denham SG and Devine K et al}},

 doi = {{10.1136/bmjopen-2021-055435}},

 volume = {{11}},

 journal = {{BMJ Open}},

 issue = {{10}},

 note = {{Accessed on 2024/12/22}}}