Cita APA (7a ed.)

Downing, A., & Locke, P. (1992). A university course in English grammar. Prentice-Hall.

Cita Chicago Style (17a ed.)

Downing, Angela, y Philip Locke. A University Course in English Grammar. New York [etc.]: Prentice-Hall, 1992.

Cita MLA (9a ed.)

Downing, Angela, y Philip Locke. A University Course in English Grammar. Prentice-Hall, 1992.