. "Gadsden Purchase of 1853" . . . "sold to the U.S. a part of Mexican territory" . . "The Gadsden Purchase" . "Gadsden Purchase" . "the Treaty of Mesilla" . . . . . . . "Gadsden Purchase Treaty" . . "Gadsden" . . . . "Gadsden Treaty" . . . . "Gadsen Purchase" . . . . . . . . "Gadsden Purchase" . "Treaty of La Mesilla or Gadsden Purchase" .