Laidi, Zaki
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Jongsoo, James Lee, author
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editor in chief, Mortimer J. Adler
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Buku Referensi
editor in cheief, Mortimer J. Adler
Encyclopedia Britanica, 1996
Buku Referensi
Adler, Mortimer J., 1902-2001 (change)
Chicago, Encyclopedia Britanica, Inc, 1990,
Buku Referensi