Thompson, Laurence C
University of Washinton, 1967
Buku Teks
Sheehan, Susan
Alfred A Knopf, 1967
Buku Teks
Vuoang, Tuan Duc
Routledge , 1994
Buku Teks
Poole, Peter A.
Cornell University Press, 1970
Buku Teks
Nguyen, Dinh-Hoa
Charles E. Tuttle Co., 1991
Buku Referensi