http://www.wtng.info/
http://www.thedirectory.org/pref/search/828.htm
https://freecallerlistings.com/prefix/
https://www.allareacodes.com/206
https://www.itu.int/oth/T0202.aspx?lang=en&parent=T0202
https://en.wikipedia.org/wiki/List_of_mobile_telephone_prefixes_by_country#cite_note-prefix_note-1