BRIEF [O.A.] Krauseneck, Valentine Author: Krauseneck, Valentine Recipient: Haeckel, Ernst Dating: 18.01.1889
POSTKARTE Krauseneck, Valentine Author: Krauseneck, Valentine Recipient: Haeckel, Ernst Dating: 16.08.1889
BRIEF [O.A.] Moleschott, Jacob Author: Moleschott, Jacob Recipient: Haeckel, Ernst Dating: 10.04.1889
BRIEF [O.A.] Moleschott, Jacob Author: Moleschott, Jacob Recipient: Haeckel, Ernst Dating: 11.07.1889
BRIEF [O.A.] Marchesetti, Carlo de Author: Marchesetti, Carlo de Recipient: Haeckel, Ernst Corporation: Museo Civico di Storia Naturale Dating: 26.12.1889
BRIEF OHNE UMSCHLAG Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 25.01.1889
BRIEF OHNE UMSCHLAG Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 28.08.1889
BRIEF OHNE UMSCHLAG Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 05.12.1889