BILDPOSTKARTE Meyer, Elisabeth; Meyer, Else Author: Meyer, Elisabeth; Meyer, Else Recipient: Haeckel, Ernst; Haeckel, Agnes Dating: ??.??.1911
BRIEF OHNE UMSCHLAG Kemna, Adolf; Vyve, B. van Author: Kemna, Adolf; Vyve, B. van Recipient: Haeckel, Ernst Corporation: Réunion Scientifique d'Anvers Dating: 14.02.1894