https://undergradresearch.gatech.edu/sites/default/files/webform/research_option_proposal_upload/_sid_/quick-list-of-united-airlines-customer%C2%AE-support-numbers-in-usa-a-comprehensive-guide%20%281%29.pdf https://undergradresearch.gatech.edu/sites/default/files/webform/research_option_proposal_upload/_sid_/complete-lists-of-united-airlines%C2%AE-customer%C2%AE-usa-support-numbers-us-an-official-detailed-guide.pdf https://undergradresearch.gatech.edu/sites/default/files/webform/research_option_proposal_upload/_sid_/contact-methods-united-airlines%C2%AE-customer-service-number-an-all-inclusive-guide.pdf https://undergradresearch.gatech.edu/sites/default/files/webform/research_option_proposal_upload/_sid_/full-list-of-official-expedi%F0%9D%93%AA%C2%AE-customer%C2%AE-service-contact-numbers-in-usa%C2%AE-the-ultimate-official-guide.pdf https://undergradresearch.gatech.edu/sites/default/files/webform/research_option_proposal_upload/_sid_/Breeze-Airways%C2%AE%EF%B8%8F-usa-contact-numbers-complete-2025-support-guide_1.pdf