สูตรคู่เดียว 2ตัวล่าง 16/05/62 (รวม2สูตร)
Your airline ticket it in fact a legally binding contract between you and the airline, though it is a contract you can rarely negotiate and is tilted heavily in the airline's favor.
from: http://ezinearticles.com/?The-Airline-Ticket-is-a-Binding-Contract&id=196160
