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Stevenson, George A.
McGraw-Hill, 1992
Buku Referensi
general editor, Sir Lawrence Gowing
Encyclopaedia Britannica, 2005
Buku Referensi
general editor, Sir Lawrence Gowing
Encyclopaedia Britannica, 2005
Buku Referensi
general editor, Sir Lawrence Gowing
Encyclopaedia Britannica, 2005
Buku Referensi