[phongthoa]

bạn tham khảo ở đây nhé
http://vnexpress.net/Vietnam/Vi-tinh...6/02/3B9E6F7B/
http://www.sohoa.net/News/Chuyen-gia/2005/02/3B9ACE5C/
http://thegioipin.com/?name=knowledg...&sectionId=122