Columbia subject headings:
Harvard subject headings:
Authors, Italian--20th century--Correspondence
Authors, Spanish--20th century--Correspondence
Boine, Giovanni, 1887-1917--Correspondence.
Unamuno, Miguel de, 1864-1936. Correspondence.
Princeton subject headings:
Authors, Italian--20th century--Correspondence.
Authors, Spanish--20th century--Correspondence.
Boine, Giovanni, 1887-1917--Correspondence.
Unamuno, Miguel de, 1864-1936--Correspondence.