The Library of Congress has digitized much of its extensive Sigmund Freud Collection, 20,000 items in all, including letters, artifacts from his personal and professional life and hundreds of interviews with colleagues, family members, patients and even his housekeeper.
The Library of Congress: Sigmund Freud Collection
Postcard: Sigmund Freud to wife Martha Freud sent on his arrival in New York for a lecture and signed also by colleagues Sandor Ferenczi, C. G. Jung and A. A. Brill, August 30, 1909
See also: Freud in America - Freud's first and only visit to the United States