Correspondenz-Karte, 1885 Nov. 7, Aistersheim, an Emo Senhor Adolpho Moller, Coimbra [manuscrito] / Dr. K. Keck.
[Brief], 1886 Feb. 4, Aistersheim, [an] Herr[n Adolfo F. Möller, Coimbra] [manuscrito] / Dr. K. Keck.
Correspondenz-Karte, 1886 März 27, Aistersheim, an Exc. Senhor Adolpho Moller, Coimbra [manuscrito] / K. Keck.
Correspondenz-K[arte], 1879 Mai 8, Wien, an Monsieur Ad. Fred. Moller, Coimbra [manuscrito] / Baron Thümen.
[Letter], 1910 May 13, Washington, [to Júlio Henriques], Coimbra [manuscrito] / David Fairchild.
[Lettre], 1898 oct. 10, Genève, [à] Monsieur le Prof. Henriques, Coimbra [manuscrito] / Eug. Autran.
[Lettre], 1899 juin 22, Valleyres, [à Júlio Henriques, Coimbra] [manuscrito] / William Barbey.
[Lettre], 1885 mars 29, Genève, [à] Monsieur [Júlio Henriques, Coimbra] [manuscrito] / Edmond Boissier.