Https://forms.business.columbia.edu/sites/forms/files-efs/webform/2023_deming_cup_nomination_and_a/_sid_/Delta-Airlines-Customer-Service-Number-1-877-245-9769.pdf https://forms.business.columbia.edu/sites/forms/files-efs/webform/2023_deming_cup_nomination_and_a/_sid_/Delta-Airlines-Customer-Service-Number-1-877-245-9769.pdf