Langer, W. L. (1952). An encyclopedia of world history: Ancient, medieval, and modern, chronologically arranged (Revised edition.). Houghton Mifflin.
Cita Chicago (17th ed.)Langer, William L. An Encyclopedia of World History: Ancient, Medieval, and Modern, Chronologically Arranged. Revised edition. Boston: Houghton Mifflin, 1952.
Cita MLA (8th ed.)Langer, William L. An Encyclopedia of World History: Ancient, Medieval, and Modern, Chronologically Arranged. Revised edition. Houghton Mifflin, 1952.
Atenció: Aquestes cites poden no estar 100% correctes.