Columbia subject headings:
Harvard subject headings:
Lenin, Vladimir Ilʹich, 1870-1924--Philosophy.
Lenin, Vladimir Ilʹich, 1870-1924. Materializm i ėmpiriokritit︠s︡izm.
Positivism.
Princeton subject headings:
Dialectical materialism.
Lenin, Vladimir Ilʹich, 1870-1924. Materializmi i empiriokrititsizm.
Positivism.