Columbia subject headings:
Gomperz, Theodor, 1832-1912.
Mill, John Stuart, 1806-1873.
Harvard subject headings:
Gomperz, Theodor, 1832-1912.
Mill, John Stuart, 1806-1873
Princeton subject headings:
Gomperz, Theodor, 1832-1912.
Mill, John Stuart, 1806-1873.