https://www.scienceforums.com/topic/97020-55-ways-to-call-to-live-agent-at-united-airlines-via-phone-email-or-chat-a-step-by-step-guide/
https://www.scienceforums.com/topic/97011-21-ways-to-speak-to-live-agent-at-united-airlines-via-phone-email-or-chat-a-step-by-step-guide/
https://www.scienceforums.com/topic/96853-sixty-ways-to-call-to-live-agent-at-air-canada-airlines-a-quick-guide/
https://www.scienceforums.com/topic/95897-05-ways-to-call-british-airways-%C2%AE%EF%B8%8F-usa-contact-numbers-%E2%80%93-a-full-detailed-guide/
https://www.scienceforums.com/topic/96877-ninety-seven-ways-to-contact-how-can-i-speak-to-someone-at-air-canada-airlines-via-callchator-email/
https://www.scienceforums.com/topic/95914-19-easy-ways-to-contact-british-airways-%C2%AE%EF%B8%8F-usa-contact-numbers-%E2%80%93-the-complete-guide/
https://regions-and-cities.europa.eu/sites/default/files/webform/multimedia_center/_sid_/aeromexico-%C2%BFcomo-hablar-con-una-persona-en-aeromexico.pdf
https://www.scienceforums.com/topic/96976-how-to-call-to-someone-at-frontier-airlines-now-the-complete-guide/