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Major characteristics of the articles (1970–2019).
| Period | A | AU | C | TC | TC/A | J |
|---|---|---|---|---|---|---|
| 1970–1979 | 7 | 11 | 2 | 813 | 116.1 | 2 |
| 1980–1989 | 13 | 19 | 2 | 904 | 69.5 | 5 |
| 1990–1999 | 16 | 45 | 7 | 579 | 36.2 | 16 |
| 2000–2009 | 91 | 259 | 31 | 3457 | 38.0 | 34 |
| 2010–2019 | 743 | 2001 | 86 | 5737 | 7.7 | 397 |
A: number of articles; AU: number of authors; C: number of countries; TC: number of citations in total articles; TC/A: number of citations by article; J: number of journals.
