TELEGRAMM Recipient: Haeckel, Ernst Corporation: Akademischer Verein Deutscher Naturhistoriker in Prag Dating: 16.02.1904
POSTKARTE Lendenfeld, Robert von Author: Lendenfeld, Robert von Recipient: Haeckel, Ernst Dating: 15.02.1904
BRIEF [O.A.] Lendenfeld, Robert von Author: Lendenfeld, Robert von Recipient: Haeckel, Ernst Dating: 02.11.1904
BRIEF [O.A.] Novak, Terese Author: Novak, Terese Recipient: Haeckel, Ernst Corporation: Zsch. Zensky Svet Dating: 10.02.1904
BRIEF [O.A.] Hohenberg, Richard Ritter von O... Author: Hohenberg, Richard Ritter von O... Recipient: Haeckel, Ernst Dating: 17.02.1904