BRIEF [O.A.] Ornstein, Bernhard Author: Ornstein, Bernhard Recipient: Haeckel, Ernst Dating: 26.11.1876
BRIEF [O.A.] Ornstein, Bernhard Author: Ornstein, Bernhard Recipient: Haeckel, Ernst Dating: 23.08.1879
BRIEF [O.A.] Ornstein, Bernhard Author: Ornstein, Bernhard Recipient: Haeckel, Ernst Dating: 30.12.1876