Cita APA (7a ed.)

Sheeler, W. D. (1991). WELCOME TO ENGLISH BOOK 4. English Language Service.

Cita Chicago Style (17a ed.)

Sheeler, Willard D. WELCOME TO ENGLISH BOOK 4. English Language Service, 1991.

Cita MLA (8a ed.)

Sheeler, Willard D. WELCOME TO ENGLISH BOOK 4. English Language Service, 1991.

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