Columbia subject headings:
Harvard subject headings:
Kropotkin, Petr Alekseevich, kni︠a︡zʹ, 1842-1921--Criticism and interpretation.
Social sciences--Philosophy--19th century.
Princeton subject headings:
Ethics.
Kropotkin, Petr Alekseevich, kni︠a︡zʹ, 1842-1921--Criticism and interpretation.
Kropotkin, Petr Alekseevich, kni︠a︡zʹ, 1842-1921. Ėtika.