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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/).
Word cloud created from abstracts of the 40 selected studies. The size of each word is proportional to the number of times it has been cited throughout the text. Note: created with wordclouds.com. Accessed on 18 September 2022.