[The following document was discovered after the microfilm edition of Thomas A. Edison Papers, Part II (1879-1886) was published and was initially published in the Supplement Series in the microfilm edition of Thomas A. Edison Papers, Part III (1887-1898). To see the location of this item in the Series Notes for Part II, use the "Which Series Notes?" button.]
This pamphlet contains testimony by Edison, Francis Jehl, Charles T. Hughes, and Charles L. Clark.
Related interference records can be found in Records of the Patent and Trademark Office (Record Group 241) in the National Archives.