BRIEF [O.A.] Krefft, Gerard Author: Krefft, Gerard Recipient: Haeckel, Ernst Corporation: Australien Museum Sydney Dating: 22.01.1874
BRIEF [O.A.] Maleohn, Frederik A... Author: Maleohn, Frederik A... Recipient: Haeckel, Ernst Dating: 10.01.1911
BRIEF [O.A.] Lendenfeld, Robert von Author: Lendenfeld, Robert von Recipient: Haeckel, Ernst Dating: 26.09.1885
BRIEF [O.A.] Lendenfeld, Robert von Author: Lendenfeld, Robert von Recipient: Haeckel, Ernst Dating: 24.04.1885