BRIEF [O.A.] Boardman, Alex J... Author: Boardman, Alex J... Recipient: Haeckel, Ernst Dating: 02.02.1876
BRIEF [O.A.] Boardman, Alex J... Author: Boardman, Alex J... Recipient: Haeckel, Ernst Dating: 16.02.1876
BRIEF [O.A.] Chandler, James E... Author: Chandler, James E... Recipient: Haeckel, Ernst Dating: 11.02.1902
BRIEF [O.A.] Chandler, James E... Author: Chandler, James E... Recipient: Haeckel, Ernst Dating: 05.05.1902