Heuduck, P. (1946). Letter to Mortimer Schwager, July 1, 1946. Saint Louis University Libraries Digitization Center.
Chicago Style aipamenaHeuduck, Paul. Letter to Mortimer Schwager, July 1, 1946. Saint Louis University Libraries Digitization Center, 1946.
MLA aipamenaHeuduck, Paul. Letter to Mortimer Schwager, July 1, 1946. Saint Louis University Libraries Digitization Center, 1946.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.