Table 9.
Results of co-occurrence of keyword analysis for the period T1, T2 & T3
| 1991–2000 (T1) | 2001–2010 (T2) | 2011–2021 (T3) | |
|---|---|---|---|
| Keywords | 1738 | 12,020 | 31,725 |
| Keywords (threshold = 15) | 15 | 151 | 546 |
| Clusters | 1 | 4 | 7 |
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