A passenger, consignor or consignee by accepting a ticket, bill of lading or written contract for carriage, with a knowledge of its terms, assents to the rate of hire, the time, place and manner of delivery therein stated. But his assent to any other modification of the carrier's rights or obligations contained in such instrument can only be manifested by his signature to the same. R.L. 1910, § 798.
Oklahoma Legal Code