Columbia subject headings:
Unamuno, Miguel de, 1864-1936--Contemporaries.
Unamuno, Miguel de, 1864-1936--Political and social views.
Harvard subject headings:
Unamuno, Miguel de, 1864-1936--Contemporaries.
Unamuno, Miguel de, 1864-1936--Political and social views.
Princeton subject headings:
Essays.
Unamuno, Miguel de, 1864-1936--Criticism and interpretation.