. . "Catalogs"@en . . . . . . . . . . . . . . . . . "United States patents of Thomas Alva Edison, June 1st, 1869 to May 20th, 1884"@en . . . . "Collection of United States patents granted to Thomas A. Edison, 1869-1884"@en . . . . . "United States patents granted to Thomas A. Edison, 1869-79"@en . . .