https://www.transfermarkt.com/100-what-day-is-the-cheapest-to-book-american-airlines-/thread/forum/696/thread_id/28504/page/1#anchor_29117
https://www.transfermarkt.com/100-what-day-is-the-cheapest-to-book-american-airlines-/thread/forum/696/thread_id/28504/page/1#anchor_29117