"NANP-wide" . . "Area code(s)" . "the destination number" . "Area code" . "Area codes" . "NANP" . . "Area Codes" . . . "North American Numbering Plan#Numbering plan areas and central offices" . "NPA-NXX" . "'''Number Format'''" . "the old dial phones" . . "exhausted" . . "Number Format" . . "North American Numbering Plan" . "North American Numbering Plan" . "+1" . "North America" . "area codes" . . "Telephone numbers in the United States" . "North American area codes" . "central office" . . . . "North American Dialing Plan" . "NXX Exchange" . "[destination number]" . "Telephone area code" . "Area codes" . "Area code(s)" . "numbering plan" . "Numbering plan" . "540-533-7607" . . "U.S. telephone numbers" . "area code" . "spell out" . "North American Numbering Plan Administration" . "Numbering Plan" . "NPA" . . "North American telephone" . . "North American Numbering Plan#Central office codes" . "NANPA" . "North American Numbering Plan (NANP)" . "North American" . . . "Area Code" . "Area" . "North American Numbering Plan Administration's" . "Area code (s)" .