BRIEF [O.A.] Chelius, Gustaf Author: Chelius, Gustaf Recipient: Haeckel, Ernst Corporation: Kammanditbolaget Chelius & Co., Bokförlag Dating: 06.03.1906
POSTKARTE Gyldén, Therese Author: Gyldén, Therese Recipient: Haeckel, Ernst; Haeckel, Agnes Dating: 30.12.1904