DeFilippo, J., & Mackey, D. (1987). Grammar plus: A basic skills course for english language learners. Addison-Wesley Publ.Comp.
Čikaški stil citiranja (17. izdanje)DeFilippo, Judy, i Daphne Mackey. Grammar Plus: A Basic Skills Course for English Language Learners. Addison-Wesley Publ.Comp, 1987.
MLA način citiranja (8. izdanje)DeFilippo, Judy, i Daphne Mackey. Grammar Plus: A Basic Skills Course for English Language Learners. Addison-Wesley Publ.Comp, 1987.
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