BRIEF OHNE UMSCHLAG Targioni Tozzetti, Ad. Author: Targioni Tozzetti, Ad. Recipient: Haeckel, Ernst Dating: 18.02.1894
BRIEF OHNE UMSCHLAG Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 14.02.1894
BRIEF OHNE UMSCHLAG Krauseneck, Gustav Adolf Author: Krauseneck, Gustav Adolf Recipient: Haeckel, Ernst Dating: 29.12.1894
BRIEF OHNE UMSCHLAG Gasco, Francesco Author: Gasco, Francesco Recipient: Haeckel, Ernst Corporation: Camera Dei Deputati Dating: 13.03.1894