Table 1.
Distribution by the year of publication.
| Year | Article count | Percentage | Year | Article count | Percentage | Year | Article count | Percentage |
|---|---|---|---|---|---|---|---|---|
| 2017 | 41 | 18.7% | 2015 | 49 | 22.4% | 2013 | 18 | 8.2% |
| 2016 | 76 | 34.7% | 2014 | 14 | 6.4% | 2012 | 21 | 9.6% |
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