Columbia subject headings:
Harvard subject headings:
Engels, Friedrich, 1820-1895
Engels, Friedrich, 1820-1895--Contributions in anthropology.
Human evolution.
Marx, Karl, 1818-1883
Marx, Karl, 1818-1883--Contributions in anthropology.
Philosophical anthropology.
Princeton subject headings:
Engels, Friedrich, 1820-1895.
Human evolution.
Marx, Karl, 1818-1883.
Philosophical anthropology.