| https://anterior-cualtos.udg.mx/sites/default/files/webform/_telefono_como_hablo_con_alguien_en_frontier_.pdf |
| https://cehd.uchicago.edu/wp-content/uploads/formidable/12/united-airlines-el-salvador.pdf |
| https://www.goodreads.com/quotes/15049697-c-mo-puedo-comunicarme-con-frontier-en-espa-ol-4718-frontier-envivo-c-mo-puedo |
| https://sites.google.com/view/volaris-telefono-sv/ |
| https://cehd.uchicago.edu/wp-content/uploads/formidable/12/frontier-telefono-el-salvador-sv.pdf |
| https://printea.eap.edu/wp-content/uploads/sites/16/2025/10/vivo-en-avianca-airlines-el-salvador.pdf |
| https://anterior-cualtos.udg.mx/sites/default/files/webform/avianca_telefono_503_como_se_llama_avianca_.pdf |
| https://www.goodreads.com/quotes/15051787-c-mo-hablo-con-alguien-en-united-llamar-a-united-desde |
