BRIEF OHNE UMSCHLAG Bleek, Auguste Author: Bleek, Auguste Recipient: Haeckel, Carl Gottlob; Haeckel, Charlotte Dating: 04.09.1866
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Carl Gottlob; Haeckel, Charlotte Dating: 19.11.1866
BRIEF OHNE UMSCHLAG Haeckel, Karl Author: Haeckel, Karl Recipient: Haeckel, Carl Gottlob; Haeckel, Charlotte Dating: 20.04.1866