Smith, Charles John
Synonyms discriminated: a dictionary of synonymous words in the English langauge
Bell and Sons, 1917
 Buku Referensi
Teaching Challenges In Indonesia: motivating students and teachers' classroom langauge
 Artikel Jurnal
Burridge, Kate
Blooming english: observations on the roots, cultivation and hybrids of the english langauge
Cambridge University Press, 2004
 Buku Teks SO
Parrot, Martin
Grammar for English language teachers
Cambridge University Press, 2003
 Buku Teks
Protherough, Robert
The making of english teachers
Open University Press, 1991
 Buku Teks SO