Cass, James
New York, Harper & Row Publishers
Buku Referensi
Berkeley University of California Press 1968
Buku Teks
Barbeau, Joseph E.
Custom book program of northeastern University , 1985
Buku Teks
Cambridge Hobsons 1987
Buku Referensi
bEIJING bEIJING dAXUE cHUBANSHE 1995
Buku Teks