https://forum.metacartel.org/t/travel-guide-aa-what-day-is-the-cheapest-to-book-american-airlines/3737
https://forum.metacartel.org/t/amtrack-trains-what-is-the-cheapest-day-of-the-week-to-buy-amtrak-tickets/3740
https://forum.metacartel.org/t/call-american-what-is-the-cheapest-day-to-fly-on-american-airlines/3739