Littlejohn, A. (1991). Writing 4. Cambridge: Cambridge University Press.
Trích dẫn kiểu ChicagoLittlejohn, Andrew. Writing 4. Cambridge: Cambridge University Press, 1991.
MLA引文Littlejohn, Andrew. Writing 4. Cambridge: Cambridge University Press, 1991.
警告：這些引文格式不一定是100％准確.