TELEGRAMM Arrhenius, Svante August Author: Arrhenius, Svante August Recipient: Haeckel, Ernst Dating: 16.02.1914
TELEGRAMM Retzius, Gustaf; Leche, Wilhelm [et al.] Author: Retzius, Gustaf; Leche, Wilhelm [et al.] Recipient: Haeckel, Ernst Dating: 17.02.1894