« Elmer Sperry Dies. Famous Inventor », New York Times, (lire en ligne, consulté le ) :
Elmer A. Sperry, inventor, died yesterday morning at St. John's Hospital, Brooklyn, from complications which set in after he had recovered from an operation for gallstones six weeks ago. He was in his seventieth year.
« Edward G. Sperry, An Industrialist. Executive of Products Firm He Founded With Father, the Gyroscope Inventor, Dies. Designed Ship Stabilizers. Held Several Directorships », New York Times, (lire en ligne, consulté le )
