Columbia subject headings:
Alas, Leopoldo, 1852-1901--Criticism and interpretation.
Philosophy, Spanish--19th century.
Harvard subject headings:
Alas, Leopoldo, 1852-1901--Criticism and interpretation.
Philosophy, Spanish--19th century.
Princeton subject headings:
Alas, Leopoldo, 1852-1901--Philosophy.
Spain--Intellectual life--19th century.