@article{Hurst_2021,
title={Vitamin D insufficiency in COVID-19 and influenza A,
and critical illness survivors: a cross-sectional study},
volume={11},
ISSN={2044-6055},
url={http://dx.doi.org/10.1136/bmjopen-2021-055435},
DOI={10.1136/bmjopen-2021-055435},
number={10},
journal={BMJ Open},
publisher={BMJ},
author={Hurst,
Emma A and Mellanby,
Richard J and Handel,
Ian and Griffith,
David M and Rossi,
Adriano G and Walsh,
Timothy S and Shankar-Hari,
Manu and Dunning,
Jake and Homer,
Natalie Z and Denham,
Scott G and Devine,
Kerri and Holloway,
Paul A and Moore,
Shona C and Thwaites,
Ryan S and Samanta,
Romit J and Summers,
Charlotte and Hardwick,
Hayley E and Oosthuyzen,
Wilna and Turtle,
Lance and Semple,
Malcolm G and Openshaw,
Peter J M and Baillie,
J Kenneth and Russell,
Clark D},
year={2021},
month=oct,
pages={e055435} }