References

1. http://en.wikipedia.org

2. Lonelyplanet.com

3. www.myvietnamvisa.com

4. https://gabon.visahq.com

5. planetware.com/tourist-attractions/israel-isr.htm

6. http://www.wwinn.org/brazil-inland-waterways

7. https://brazil.visahq.com/customs/

8. http://www.touropia.com/tourist-attractions-in-brazil/

9. http://www.tradingeconomics.com/greece/air-transport-passengers-carried.html

10. https://greece.visahq.com/customs/

11. http://www.lonelyplanet.com

12. http://www.planetware.com/tourist-attractions/california-usca.htm