30 visiting now: 7 USA 
6 China 
6 Belgium 
4 India 
3 Singapore 
1 Pakistan 
1 Iran 
1 Taiwan 
1 Nigeria 
6 China 6 Belgium 4 India 3 Singapore 1 Pakistan 1 Iran 1 Taiwan 1 Nigeria 6 China 6 Belgium 4 India 3 Singapore 1 Pakistan 1 Iran 1 Taiwan 1 Nigeria