BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Siebold, Carl Theodor Ernst von Dating: 17.02.1875
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Siebold, Carl Theodor Ernst von Dating: 26.10.1875
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Siebold, Carl Theodor Ernst von Dating: 07.11.1875