Https://mechatronics.ucmerced.edu/sites/g/files/ufvvjh1226/f/webform/what-is-the-boarding-process-for-delta-airlinesfaq-supportr.pdf https://mechatronics.ucmerced.edu/sites/g/files/ufvvjh1226/f/webform/what-is-the-boarding-process-for-delta-airlinesfaq-supportr.pdf