Nicholson, Margaret
Oxford University Press, 1957
Buku Referensi
Black, Henry Campbell
West Publishing, 1990
Buku Referensi
Black, Henry Campbell
West Publishing, 1985
Buku Referensi
Black, Henry Campbell
West Publishing, 1990
Buku Teks
Plano, Jack C.
Holt, Rinehart and Winston, 1985
Buku Referensi