APA (7th ed.) Citation

Johnson, T. H. (1966). The Oxford companion to American history / by T.H. Johnson. O.U.P..

Chicago Style (17th ed.) Citation

Johnson, T. H. The Oxford Companion to American History / by T.H. Johnson. O.U.P., 1966.

MLA (9th ed.) Citation

Johnson, T. H. The Oxford Companion to American History / by T.H. Johnson. O.U.P., 1966.

Warning: These citations may not always be 100% accurate.