Kench, A. B.
The language of English business letters / A. B. Kench
Macmillan, 1972
 Buku Teks SO
Eliza Margaretha
Automatic english to Indonesia lexical mapping using latent semantic analysis
Fakultas Ilmu Komputer Universitas Indonesia, 2008
 UI - Skripsi Open
English Studies : a journal of English letters and philology
Amsterdam : Swets & Zeitlinger
 Majalah, Jurnal, Buletin
Phythian, B.A.
English grammar / B. A. Phythian
Hodder & Stoughton, 1980
 Buku Teks SO
Jasckson, Howard
Grammar and meaning : a semantic approach to English grammar
Longman, 1990
 Buku Teks SO