BRIEF OHNE UMSCHLAG Guyet, Adolph Author: Guyet, Adolph Recipient: Haeckel, Ernst Corporation: Großherzogliches Sächs. Staatsministerium, Department des Kultus Dating: 15.08.1890
BRIEF OHNE UMSCHLAG Guyet, Adolph Author: Guyet, Adolph Recipient: Haeckel, Ernst Corporation: Großherzogliches Sächs. Staatsministerium, Department des Kultus Dating: 17.12.1890