BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 22.11.1910
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 30.11.1910
POSTKARTE Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 12.04.1911
TELEGRAMM Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 17.05.1911
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: ??.??.1911
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 12.02.1913
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 30.11.1913
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 04.12.1913
BRIEF [O.A.] Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 08.12.1913
TELEGRAMM Gabriel, Gábor Raimund Author: Gabriel, Gábor Raimund Recipient: Haeckel, Ernst Dating: 10.12.1913