POSTKARTE Hinderdael, Irmgard van Author: Hinderdael, Irmgard van Recipient: Haeckel, Ernst Dating: 31.12.1913
POSTKARTE Hinderdael, Irmgard van Author: Hinderdael, Irmgard van Recipient: Haeckel, Ernst Dating: 09.05.1918
BILDPOSTKARTE Hinderdael, Irmgard van Author: Hinderdael, Irmgard van Recipient: Haeckel, Ernst Dating: 16.02.1914