https://ia600606.us.archive.org/4/items/official_delta_guide_202602/American-Airlines-global-customer-support-numbers.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/Delta-Airlines-refund-customer-service-phones.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/american-customer-service-usa-phone-number.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/complete-updated-guide-of-delta-airlines-customer-service-contact-numbers-assitance.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/complete-updated-guide-of-united-customer-service-contact-numbers-assitance.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/delta-airlines-live-person-customer-service-guide.pdf
https://ia600606.us.archive.org/4/items/official_delta_guide_202602/united-airlines-refund-customer-service-phone.pdf