Https://ppf.ucsf.edu/sites/ppf.ucsf.edu/files/webform/complete-list-of-united-airlines-customer-service-in-the-usa%E2%80%93-the-ultimate-official-help-guide.pdf https://ppf.ucsf.edu/sites/ppf.ucsf.edu/files/webform/complete-list-of-united-airlines-customer-service-in-the-usa%E2%80%93-the-ultimate-official-help-guide.pdf