ANSICHTSKARTE Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 12.04.1904
ANSICHTSKARTE Bresgen, Maximilian Author: Bresgen, Maximilian Recipient: Haeckel, Ernst Dating: 12.02.1899
ANSICHTSKARTE Haeckel, Walther; Haeckel, Josefa Author: Haeckel, Walther; Haeckel, Josefa Recipient: Haeckel, Ernst; Haeckel, Agnes [Eltern] Dating: 12.05.1909