[1] Keyes, Scott. “10 Flight Booking Hacks to Score Cheap Flights and Travel for Less: Scott’s Cheap Flights.” Scott’s Cheap Flights, Scott’s Cheap Flights, 11 Sept. 2019, scottscheapflights.com/guides/flight-hacks.
[2] Chitty, Tom. “This Is How Airlines Price Tickets.” CNBC, CNBC LLC, 3 Aug. 2018, 11:59 AM, www.cnbc.com/2018/08/03/how-do-airlines-price-seat-tickets.html.
[3] McMahon, Shannon. “7 Expert Airplane Seat Hacks to Boost Comfort on Long Flights.” SmarterTravel, Smarter Travel Media LLC, 11 July 2018, www.smartertravel.com/airplane-seat-hacks/.
[4] https://images.app.goo.gl/8u5Ai7xSJ6TT7cA28 by Airspace Technology.