Crabb, George
New York Grosset and Dunlap [t.th.]
Buku Teks
edited by G. Elgie Christ
Frederick Warne and Co, 1960
Buku Referensi
Smith, Charles John
Bell and Sons, 1917
Buku Referensi
C. Bleijenberg
Uitgeverij Scuyt N.V., 1949
Buku Teks
Terence Wade
Cambridge University Press, 2004
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