edited by Frank A. Sloan
Cambridge University Press, 1996
Buku Teks
Fishman, Betty G., author
Thomas Y. Crowell, 1969
Buku Teks
Rodgers, Harrell R.
M.E. Sharpe, Inc., 1986
Buku Teks
Keiser, Norman F., author
John Wiley & Sons, 1964
Buku Teks
Garvey, George E., author
Greenwood Press, 1990
Buku Teks