Chao, Yuen Ren, 1892-
Harvard University Press, 1962
Buku Referensi
Chao, Yuen Ren, 1892-
University of California Press, 1968
Buku Teks SO
Halliday, M.A.K.
Oxford University Press, 1989
Buku Teks SO
Cambridge University Press, 2007
eBooks
Underhill, Nic
Cambridge University Press, 1993
Buku Teks SO