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The top 10 countries and regions in terms of publications.
| Countries/Regions | Number of manuscripts | Centralities (Rank) | Year |
| United States | 586 | 0.18 (2) | 2007 |
| China | 447 | 0.01 (30) | 2009 |
| England | 322 | 0.31 (1) | 2009 |
| Australia | 219 | 0.17 (3) | 2008 |
| Japan | 206 | 0.03 (20) | 2008 |
| South Korea | 162 | 0.03 (21) | 2010 |
| Germany | 149 | 0.05 (11) | 2008 |
| Spain | 131 | 0.13 (4) | 2012 |
| Canada | 130 | 0.07 (5) | 2012 |
| Sweden | 121 | 0.04 (15) | 2010 |
