World Book, Inc, & IBM Corp. (1998). 1999 World Book international deluxe English edition. IBM.
Chicago Style aipamenaWorld Book, Inc, and IBM Corp. 1999 World Book International Deluxe English Edition. Ireland: IBM, 1998.
MLA aipamenaWorld Book, Inc, and IBM Corp. 1999 World Book International Deluxe English Edition. IBM, 1998.
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