APA (7th ed.) Citation

Upton, C., & Widdowson, J. D. A. (1996). An atlas of English dialects. Oxford Univ. Press.

Chicago Style (17th ed.) Citation

Upton, Clive, and John D. A. Widdowson. An Atlas of English Dialects. Oxford [u.a.]: Oxford Univ. Press, 1996.

MLA (9th ed.) Citation

Upton, Clive, and John D. A. Widdowson. An Atlas of English Dialects. Oxford Univ. Press, 1996.