Fuller, Harry J.
Holt Rinehart and Winston, 1963
Buku Teks
Dutta, A.C.
Oxford University Press, 1994
Buku Teks
Greulach, Victor A.
John Wiley & Sons, 1966
Buku Teks
Laetsch, Watson M.
Little, Brown, 1979
Buku Teks
Wilson, Carl L.
Holt, Rinehart and Winston, 1962
Buku Teks