Gruchmann, Lothar
Munchen : Deutscher Taschenbuch Verlag GmbH, 1974
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Muller, K.A.
Berlin Knaur 1936
Buku Teks
Jongsoo, James Lee, author
Palgrave Macmillan, 2006
Buku Teks
Adler, Mortimer J., editor in chief
Chicago, Encyclopedia Britanica, Inc, 1990, 1994
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Mortimer J. Adler, editor in chief ; Clifton Fadiman, Philip W. Goetz, associate editors
Encyclopedia Britanica, 1990
Buku Referensi