BRIEF [O.A.] Blochmann, Friedrich Author: Blochmann, Friedrich Recipient: Haeckel, Ernst Dating: 24.10.1892
BRIEF [O.A.] Blochmann, Friedrich Author: Blochmann, Friedrich Recipient: Haeckel, Ernst Corporation: Zoologisches Institut der Grossherz. Universität Rostock Dating: 07.11.1892
BRIEF [O.A.] Blochmann, Friedrich Author: Blochmann, Friedrich Recipient: Haeckel, Ernst Dating: 10.11.1892