United States. Library of Congress. Library of Congress subject heading. [s.n.].
Cita Chicago (17th ed.)United States. Library of Congress. Library of Congress Subject Heading. [s.l: [s.n.].
Cita MLA (9th ed.)United States. Library of Congress. Library of Congress Subject Heading. [s.n.].
Atenció: Aquestes cites poden no estar 100% correctes.