https://preussenjournal.de/forum/topic/fifteen-ways-to-call-how-to-contact-someone-at-air-canada-a-step-by-step-guide/#postid-15517
https://www.purplepass.com/events/325901-final-list-of-american-airlines-customer%C2%AE-contact–jul-28th-2025
https://choice.community/t/frontier-airlines-contact-to-live-agent-at-frontier-airlines-usa-live-customer-support-numbers/33910
https://www.purplepass.com/events/325958-dial-quickbooks-premier-plus-support-for-fixes%2C-er-jul-28th-2025
https://choice.community/t/delta-airlines-usa-customer-support-numbers-2025-in-full-detail-by-support-for-assistance-new/33901