BRIEF [O.A.] Dreyer, Friedrich Author: Dreyer, Friedrich Recipient: Haeckel, Ernst Dating: 10.12.1884
BRIEF [O.A.] Eisenhardt, Friedr... Author: Eisenhardt, Friedr... Recipient: Haeckel, Ernst Dating: 10.03.1917
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 24.12.1874
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 30.12.1880
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 27.08.1881
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 29.12.1882
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 25.08.1883
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 24.12.1883
BRIEF OHNE UMSCHLAG Hertwig, Richard Author: Hertwig, Richard Recipient: Haeckel, Ernst Dating: 08.10.1871
BRIEF OHNE UMSCHLAG Hertwig, Oscar Author: Hertwig, Oscar Recipient: Haeckel, Ernst Dating: 29.07.1870