BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 30.03.1914
POSTKARTE Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 18.05.1914
POSTKARTE Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 19.08.1914
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 20.10.1914
POSTKARTE Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 01.01.1915
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 15.02.1915
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 15.02.1915
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 28.09.1915
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 22.10.1915
BRIEF [O.A.] Thoden van Velzen, S... K... Author: Thoden van Velzen, S... K... Recipient: Haeckel, Ernst Dating: 24.12.1915