BRIEF OHNE UMSCHLAG Tivadary, Kormos Author: Tivadary, Kormos Recipient: Haeckel, Ernst Dating: 30.12.1901
BRIEF [O.A.] Caniy, W... [?] Author: Caniy, W... [?] Recipient: Haeckel, Ernst Corporation: Vallás és Közoktatásügyi Dating: 07.10.1896
BRIEF OHNE UMSCHLAG Teszóck, Charles A. Author: Teszóck, Charles A. Recipient: Haeckel, Ernst Dating: 23.02.1900
BRIEF [O.A.] Tarczay, Ludwig Author: Tarczay, Ludwig Recipient: Haeckel, Ernst Corporation: Vilagossag Dating: 12.06.1904