APA
World Book I., . (1986). The World Book Encyclopedia. U.S.A: World Book, Inc.
Chicago
World Book Inc, . 1986. The World Book Encyclopedia. U.S.A: World Book, Inc.
Harvard
World Book I., . (1986). The World Book Encyclopedia. U.S.A: World Book, Inc.
MLA
World Book Inc, . The World Book Encyclopedia. U.S.A: World Book, Inc. 1986.
