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Buku Referensi
edited by L.S. Blake
Butterworth, 1994
Buku Referensi
edited by L.S. Blake
Butterworth, 1986
Buku Referensi
edited by Leonard D. White
University of Chicago Press, 1945
Buku Teks
Chapman, Richard A., author
Constable, 1970
Buku Teks