Columbia subject headings:
Vallejo, César, 1892-1938--Criticism and interpretation.
Vallejo, César, 1892-1938--Political and social views.
Harvard subject headings:
Politics in literature.
Religion in literature.
Science in literature.
Vallejo, César, 1892-1938--Criticism and interpretation.
Princeton subject headings:
Vallejo, César, 1892-1938--Criticism and interpretation.
Vallejo, César, 1892-1938--Political and social views.