Cita APA (7th ed.)
Witherspoon, A. (1973). Common errors in english and how to avoid them. Littlefield.
Cita Chicago (17th ed.)
Witherspoon, Alexander. Common Errors in English and How to Avoid Them. New Jersey: Littlefield, 1973.
Cita MLA (9th ed.)
Witherspoon, Alexander. Common Errors in English and How to Avoid Them. Littlefield, 1973.
Atenció: Aquestes cites poden no estar 100% correctes.