BRIEF OHNE UMSCHLAG Delprat, Theodore Author: Delprat, Theodore Recipient: Haeckel, Ernst Dating: 14.02.1906
BRIEF OHNE UMSCHLAG Delprat, Theodore Author: Delprat, Theodore Recipient: Haeckel, Ernst Dating: 30.12.1906
BRIEF OHNE UMSCHLAG Bernelot Moens, Herman Marie Author: Bernelot Moens, Herman Marie Recipient: Haeckel, Ernst Dating: 13.07.1906