BRIEF OHNE UMSCHLAG Becker, Daniel Georg Author: Becker, Daniel Georg Recipient: Haeckel, Ernst Dating: 30.09.1902
BRIEF OHNE UMSCHLAG Becker, Daniel Georg Author: Becker, Daniel Georg Recipient: Haeckel, Ernst Dating: 04.10.1902
BRIEF [O.A.] Lo Bianco, Salvatore Author: Lo Bianco, Salvatore Recipient: Haeckel, Ernst Dating: 19.08.1902
BRIEF [O.A.] Lo Bianco, Salvatore Author: Lo Bianco, Salvatore Recipient: Haeckel, Ernst Dating: 27.12.1902
BRIEF OHNE UMSCHLAG Korsch, Carl August Author: Korsch, Carl August Recipient: Haeckel, Ernst Dating: 04.03.1902
BRIEF [O.A.] Beck, Alberto Author: Beck, Alberto Recipient: Haeckel, Ernst Corporation: Mineral de San Sebastian Dating: 18.01.1902
BRIEF OHNE UMSCHLAG Beck, Alberto Author: Beck, Alberto Recipient: Haeckel, Ernst Corporation: Mineral de San Sebastian Dating: 05.12.1902
BILDPOSTKARTE Bardeleben, Karl von et al. Author: Bardeleben, Karl von et al. Recipient: Haeckel, Ernst Dating: 27.10.1902
BRIEF OHNE UMSCHLAG Hooper, Charles E. Author: Hooper, Charles E. Recipient: Haeckel, Ernst Corporation: The Rationalist Press Association Dating: 27.08.1902