BRIEF [O.A.] Gubernatis, Graf Angelo de Author: Gubernatis, Graf Angelo de Recipient: Haeckel, Ernst Dating: 23.02.1892
BRIEF [O.A.] Krauseneck, Valentine Author: Krauseneck, Valentine Recipient: Haeckel, Ernst Dating: 10.05.1892
BRIEF [O.A.] Krauseneck, Heinrich Author: Krauseneck, Heinrich Recipient: Haeckel, Ernst Dating: 16.07.1892
BRIEF [O.A.] Krauseneck, Heinrich Author: Krauseneck, Heinrich Recipient: Haeckel, Ernst Dating: 19.09.1892
BRIEF [O.A.] Pizzoli, Ugo Author: Pizzoli, Ugo Recipient: Haeckel, Ernst Corporation: Comitato per il Monumento a Marcello Malpighi Dating: 16.05.1892
BRIEF [O.A.] Aschieri, Laurent Author: Aschieri, Laurent Recipient: Haeckel, Ernst Dating: 04.04.1892