https://support.google.com/edu/classroom/thread/337939207?hl=en&sjid=2443166422982699917-NA

https://community.whattoexpect.com/forums/austin-parents/topic/10-easy-ways-to-speak-to-delta-airlines-customer-support-169559032.html

https://airlinesdesk.helpkit.so/new-collection/4ByNMePe5h3WhTrz7o3ewK/lufthansa-contact-number/4ByNMePe5gAkTaJeBht3L5

https://support.google.com/calendar/thread/337938761?hl=en&sjid=2990643992183371533-NC

https://support.google.com/edu/classroom/thread/337938702?hl=en&sjid=2443166422982699917-NA

https://www.anime-planet.com/users/enemy111/lists/como-llamar-a-delta-airlines-en-mexico-d-1314969

https://support.google.com/youtubekids/thread/337938414?hl=en&sjid=16991767604571445999-NC

https://support.google.com/nonprofits/thread/337937257?hl=en&sjid=6638825563309797904-NC

http://forums.serebii.net/threads/7-ways-to-get-sri-lankan-airlines-booking-support-via-phone-chat-and-online-portals.782279/

https://support.google.com/edu/classroom/thread/337938260?hl=en&sjid=2443166422982699917-NA