POSTKARTE Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 01.01.1896
BRIEF [O.A.] Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 19.12.1893
BRIEF [O.A.] Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 23.02.1894
BRIEF [O.A.] Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 26.02.1895
BRIEF [O.A.] Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 06.10.1895
POSTKARTE Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 04.03.1895
POSTKARTE Preyer, William Thierry Author: Preyer, William Thierry Recipient: Haeckel, Ernst Dating: 27.04.1895