PLoS One
http://www.plosone.org/
[Accessed 7 Dec 2019]

Visual inspection of vaccine storage conditions in general practices: A study of 75 vaccine refrigerators
Anika Thielmann, Marie-Therese Puth, Birgitta Weltermann
Research Article | published 03 Dec 2019 PLOS ONE
https://doi.org/10.1371/journal.pone.0225764