BRIEF MIT UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 07.06.1884
BRIEF MIT UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 15.01.1885
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 05.06.1885
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 26.12.1886
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 26.12.1886
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 10.01.1889
BRIEF MIT UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 22.01.1890
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 27.12.1890
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 08.10.1872
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Strasburger, Eduard Dating: 10.09.1873