BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 15.02.1899
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 15.02.1900
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 08.05.1900
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 01.11.1901
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 26.10.1903
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 14.02.1904
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 14.02.1904
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 14.02.1906
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 18.07.1908
BRIEF OHNE UMSCHLAG Kükenthal, Willy Author: Kükenthal, Willy Recipient: Haeckel, Ernst Dating: 01.09.1914