BRIEF [O.A.] Sutton, A... R... Author: Sutton, A... R... Recipient: Haeckel, Ernst Dating: 22.10.1892
BRIEF [O.A.] Sutton, A... R... Author: Sutton, A... R... Recipient: Haeckel, Ernst Dating: 02.08.1892
BRIEF [O.A.] Sutton, A... R... Author: Sutton, A... R... Recipient: Haeckel, Ernst Corporation: The Ernst Haeckel Club Dating: 28.06.1892
BRIEF [O.A.] Sutton, A... R... Author: Sutton, A... R... Recipient: Haeckel, Ernst Corporation: The Ernst Haeckel Club Dating: 26.06.1893