https://support.google.com/admanager/thread/336016109?hl=en&sjid=12972302428690942390-NC

https://support.google.com/admanager/thread/336000308?hl=en&sjid=5041030535989905753-NC

https://c.mi.com/global/post/1616019/How_do_I_complain_to_Expedia

https://c.mi.com/global/post/1393393/What_is_the_24-hour_rule_with_Lufthansa

https://support.google.com/admanager/thread/336112020?hl=en&sjid=6249522776662601593-NC

https://c.mi.com/global/post/1616044/fAQSpolicyIs_Expedia_really_free_cancellation

https://c.mi.com/global/post/1393358/_How_to_save_money_on_%F0%9D%94%B8%F0%9D%95%9D%F0%9D%95%9D%F0%9D%95%96%F0%9D%95%98%F0%9D%95%9A%F0%9D%95%92%F0%9D%95%9F%F0%9D%95%A5

http://forum.dimensionengineering.com/topic/14872-how-to-talk-to-a-real-person-at-united-airlines-%E2%80%93-full-phone-guide/

https://www.goodreads.com/quotes/12699911-how-do-i-ask-a-question-on-expedia-to-ask

https://c.mi.com/global/post/1393393/What_is_the_24-hour_rule_with_Lufthansa