Kachru, Yamuna
Cultures, contexts, and world englishes
Routledge, 2008
 Buku Teks
Rivers-Smith, S.
Progress and conquest book I : the creation and the world around us
Oxford University Press, 1951
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Webster's New World dictionary and thesaurus
compiled by the editors of Webster's New World Dictionaries ; Michael Agnes, editor in chief ; with principal thesaurus text by Charlton Laird
Houghton Mifflin Harcourt, 2013
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Straus, Jane
The blue book of grammar and punctuation : an easy-to-use guide with clear rules, real-world examples, and reproducible quizzes / Jane Straus
Jossey-Bass, 2008
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The world book dictionary
edited by Clarence L. Barnhart and Robert K. Barnhart
World Book-Childcraft International, 1978
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