BRIEF [O.A.] Beck, Alberto Author: Beck, Alberto Recipient: Haeckel, Ernst Corporation: Mineral de San Sebastian Dating: 18.03.1903
BRIEF [O.A.] Zentella, Arcadio Author: Zentella, Arcadio Recipient: Haeckel, Ernst Corporation: Instrucción Pública Dating: 08.02.1910
BRIEF [O.A.] Zentella, Arcadio Author: Zentella, Arcadio Recipient: Haeckel, Ernst Corporation: Instrucción Pública Dating: 26.08.1908
BRIEF [O.A.] Beck, Alberto Author: Beck, Alberto Recipient: Haeckel, Ernst Corporation: Mineral de San Sebastian Dating: 18.01.1902
BRIEF [O.A.] Beck, Alberto Author: Beck, Alberto Recipient: Haeckel, Ernst Corporation: Mineral de San Sebastian Dating: 11.05.1903
BRIEF [O.A.] Rovirosa, F... Lacroix Author: Rovirosa, F... Lacroix Recipient: Haeckel, Ernst Dating: 02.03.1909
BRIEF [O.A.] Rovirosa, F... Lacroix Author: Rovirosa, F... Lacroix Recipient: Haeckel, Ernst Dating: 01.??.1909
BRIEF [O.A.] Rovirosa, F... Lacroix Author: Rovirosa, F... Lacroix Recipient: Haeckel, Ernst Dating: 29.09.1909
BRIEF [O.A.] Herrera, Alfonso L... Author: Herrera, Alfonso L... Recipient: Haeckel, Ernst Corporation: Museo Nacional Dating: 19.10.1895