BRIEF OHNE UMSCHLAG Engelmann, Theodor Wilhelm Author: Engelmann, Theodor Wilhelm Recipient: Haeckel, Ernst Dating: 04.01.1890
BRIEF [O.A.] Meyer Author: Meyer Recipient: Haeckel, Ernst Corporation: Bibliographisches Institut Dating: 06.09.1890
BRIEF [O.A.] Meyer Author: Meyer Recipient: Haeckel, Ernst Corporation: Bibliographisches Institut Dating: 21.03.1890
BRIEF [O.A.] Reinicke, Emanuel Author: Reinicke, Emanuel Recipient: Haeckel, Ernst Corporation: Wilhelm Engelmann Verlagsbuchhandlung Dating: 01.07.1890
BRIEF [O.A.] Reinicke, Emanuel Author: Reinicke, Emanuel Recipient: Haeckel, Ernst Corporation: Wilhelm Engelmann Verlagsbuchhandlung Dating: 08.07.1890
BRIEF OHNE UMSCHLAG Mühl, Karl Author: Mühl, Karl Recipient: Haeckel, Ernst Corporation: Redaktion von Meyers Reisebüchern; Bibliogr. Inst. Dating: 15.10.1890