BRIEF [O.A.] Franken, O... D... Author: Franken, O... D... Recipient: Haeckel, Ernst Dating: 18.04.1907
BRIEF [O.A.] Bols, Erven Lucas Author: Bols, Erven Lucas Recipient: Haeckel, Ernst Corporation: Amsterdamsche Likeurstokerij 'T Lootsje' Dating: 13.12.1907
BRIEF OHNE UMSCHLAG Mulder, J. A., de Villeneuve Author: Mulder, J. A., de Villeneuve Recipient: Haeckel, Ernst Dating: 14.05.1907
BRIEF [O.A.] Calker, F... I... P... van Author: Calker, F... I... P... van Recipient: Haeckel, Ernst Dating: 06.03.1907
BRIEF [O.A.] Kreunen, H... M... Author: Kreunen, H... M... Recipient: Haeckel, Ernst Dating: 12.03.1907
BRIEF [O.A.] Kerbert, Coenraad Author: Kerbert, Coenraad Recipient: Haeckel, Ernst Corporation: Koninklijk Zoologisch Genootschap Dating: 13.12.1907
BRIEF [O.A.] Kerbert, Coenraad Author: Kerbert, Coenraad Recipient: Haeckel, Ernst Corporation: Koninklijk Zoologisch Genootschap Dating: 19.11.1907
BRIEF OHNE UMSCHLAG Albada, B. L. van Author: Albada, B. L. van Recipient: Haeckel, Ernst Dating: 06.11.1907