https://central.xero.com/s/question/0D58V00009nRJorSAG/united-airlinescancellation-refundwhat-is-the-cancellation-policy-for-united-airlines
https://central.xero.com/s/question/0D58V00009nRHzrSAG/get-delta-refundcan-you-cancel-a-delta-flight-free-of-charge-23×8
https://www.devex.com/people/what-is-the-senior-discount-age-for-southwest-airlines-age-relaxation-2185980
https://www.devex.com/people/expedia-quick-refund-policy-is-expedia-actually-fully-refundable-2185952