Halliday, M.A.K.
Spoken and written language
Oxford University Press, 1989
 Buku Teks
Jos, Mullie
Structural principles of the Chinese language : an introduction to the spoken language
The Bureau of Engraving and Printing, 1932
 Buku Teks
Underhill, Nic
Testing spoken language: a handbook of oral testing techniques
Cambridge University Press, 1993
 Buku Teks
Teguh Narutomo
Eastern indonesia incorporated policy strategy in eastern indonesia
Kementerian Dalam Negeri RI, 2017
 Artikel Jurnal
Curme, George O
A Grammar of the German language: designed for a thorough and practical study of the language as spoken and written to-day / George O Curme
Macmillan, 1913
 Buku Teks