Https://mcmanuslab.ucsf.edu/sites/mcmanuslab.ucsf.edu/files/2025-07/american-airlines-usa-contact-numbers-a-comprehensive-guide1.pdf https://mcmanuslab.ucsf.edu/sites/mcmanuslab.ucsf.edu/files/2025-07/american-airlines-usa-contact-numbers-a-comprehensive-guide1.pdf