Columbia subject headings:
Harvard subject headings:
Brentano, Franz, 1838-1917--Correspondence.
Fechner, Gustav Theodor, 1801-1887--Correspondence.
Philosophers--Germany--Correspondence
Psychophysiology.
Princeton subject headings:
Brentano, Franz, 1838-1917--Correspondence.
Fechner, Gustav Theodor, 1801-1887--Correspondence.
Philosophers--Germany--Correspondence.
Psychophysiology.