Langan, J. (2009). English essentials: What every college student needs to know about grammar, punctuation, and usage. New York: McGraw-Hill Companies,Incorporated.
Trích dẫn kiểu ChicagoLangan, John. English Essentials: What Every College Student Needs to Know About Grammar, Punctuation, and Usage. New York: McGraw-Hill Companies,Incorporated, 2009.
Trích dẫn MLALangan, John. English Essentials: What Every College Student Needs to Know About Grammar, Punctuation, and Usage. New York: McGraw-Hill Companies,Incorporated, 2009.
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