Siegel, Eli
Definition Press, 1981
Buku Teks
Cedes, George
Oxford University Press, 1963
Buku Teks
Gardiner, Samuel Rawson
Longmans, Green, 1890
Buku Teks
Means, Gardiner C.
Harper & Brothers Publishers, 1962
Buku Teks
Gardiner, William P.
Prentice-Hall, 1997
Buku Teks