APA aipamena

Preston, D. R. (1988). Varieties of American English ( Teacher's handbook ). Washington, D.C: United States Department of State.

Chicago Style aipamena

Preston, Dennis R. Varieties of American English ( Teacher's Handbook ). Washington, D.C: United States Department of State, 1988.

MLA aipamena

Preston, Dennis R. Varieties of American English ( Teacher's Handbook ). Washington, D.C: United States Department of State, 1988.

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