Higham, J., Gilbert, F., & Krieger, L. (1965). History. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Higham, John, Felix Gilbert, agus Leonard Krieger. History. Englewood Cliffs, N.J: Prentice-Hall, 1965.
Lua MLA (9ú heag.)Higham, John, et al. History. Prentice-Hall, 1965.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.