BRIEF [O.A.] Hubrecht, Ambrosius A... W... Author: Hubrecht, Ambrosius A... W... Recipient: Haeckel, Ernst Dating: 16.06.1878
BRIEF [O.A.] Hubrecht, Ambrosius A... W... Author: Hubrecht, Ambrosius A... W... Recipient: Haeckel, Ernst Dating: 12.11.1889
BRIEF [O.A.] Hubrecht, Ambrosius A... W... Author: Hubrecht, Ambrosius A... W... Recipient: Haeckel, Ernst Corporation: Nederlandsche Dierkundige Vereeniging (Netherland Zoological Society) Dating: 25.09.1894
BRIEF [O.A.] Hubrecht, Ambrosius A... W... Author: Hubrecht, Ambrosius A... W... Recipient: Haeckel, Ernst Dating: 05.11.1896