Rank Country Documents Citations
1 The United States (North America) 1248 39027
2 China (Asia) 631 11065
3 South Korea (Asia) 293 5276
4 Belgium (Europe) 272 17501
5 Japan (Asia) 257 7726
6 Italy (Europe) 247 6129
7 England (Europe) 237 12219
8 Germany (Europe) 217 8170
9 Canada (North America) 173 6273
10 Sweden (Europe) 145 8381