BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Anna Dating: 24.12.1859
BRIEF OHNE UMSCHLAG Gegenbaur, Carl Author: Gegenbaur, Carl Recipient: Haeckel, Ernst Dating: 07.04.1873
BRIEF [O.A.] Bartels, Edmund von Author: Bartels, Edmund von Recipient: Haeckel, Ernst Dating: 27.11.1860
BRIEF [O.A.] Bartels, Edmund von Author: Bartels, Edmund von Recipient: Haeckel, Ernst Dating: 11.05.1861
BRIEF [O.A.] Bartels, Edmund von Author: Bartels, Edmund von Recipient: Haeckel, Ernst Dating: 20.07.1861
BRIEF [O.A.] Bartels, Edmund von Author: Bartels, Edmund von Recipient: Haeckel, Ernst Dating: 06.09.1861
BRIEF [O.A.] Fisichella, Francesco Author: Fisichella, Francesco Recipient: Haeckel, Ernst Corporation: Regia Universitá di Messina Dating: 03.04.189?
BRIEF [O.A.] Schultze, Leonhard Author: Schultze, Leonhard Recipient: Haeckel, Ernst Dating: 18.04.1900
BRIEF [O.A.] Schultze, Leonhard Author: Schultze, Leonhard Recipient: Haeckel, Ernst Dating: 28.05.1900
BRIEF [O.A.] Schultze, Leonhard Author: Schultze, Leonhard Recipient: Haeckel, Ernst Dating: 29.04.1900