APA ציטוט

Roberts, P. D. (1987). Plan English a user's guide. USA: Penguin Books.

Trích dẫn kiểu Chicago

Roberts, Philip Davies. Plan English a User's Guide. USA: Penguin Books, 1987.

ציטוט MLA

Roberts, Philip Davies. Plan English a User's Guide. USA: Penguin Books, 1987.