https://nbss.edu/wp-content/uploads/formidable/12/Complete-List-of-United-24-7-Customer-Service-Full-Brief-Guide.pdf

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/full-list-of-southwest-airlines-customer-service-24-7-help-desk-numbers-a-complete-guide.pdf

https://www.pixiv.net/novel/show.php?id=25908535

https://www.pixiv.net/novel/show.php?id=25908484

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/complete-list-of-jetblue-airlines-usa-customer-service-contact-numbers.pdf

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/full-list-of-united-airlines-tm-customer-usa-direct-contact-numbers-live-all-in-guide.pdf

http://fbrnvolunteers.org/forms/data/form_7675/files/element_22_3acf6166dfce27de70b816f24533257d-quick-official-list-of-air-canada-customer-service-24-7-live-person-support-numbers-a-complete-guide.pdf.tmp

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/full-list-of-hawaiian-airlines-customer-service-contact-numbers-in-the-usa-a-comprehensive-guide.pdf

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/complete-list-of-air-canada-airlines-usa-customer-service-contact-numbers.pdf

https://www.osn.iaa.csic.es/sites/default/files/solicitudes/full-list-of-lufthansa-airlines-tm-customer-usa-direct-contact-numbers-live-all-in-guide.pdf