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. 2022 Nov 24;30(3):5502–5515. doi: 10.1007/s11356-022-24379-6

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© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

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Fig. 4 — Density diagram of bibliographic coupling of documents (minimum number of citations of a document of the 312 documents: 148, meet the threshold: 11, clusters: 4, links: 21, total link strength: 56, weights: citations, VosViewer 1.6.18)