. 2021 Dec 30;19(1):353. doi: 10.3390/ijerph19010353
© 2021 by the authors.
Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Figure 7.
Co-keywords analysis of global high-frequency.