https://phmsociety.org/phm-forums/topic/1-855-550-0971american-airlines-cancellations-policy-and-refunds-faqs/
https://intercom.help/esapnol-telefono/en/articles/10807175-politica-de-1-866-838-4906-cancelacion-de-expedia-expedia-es-realmente-la-cancelacion-gratuita