Grammar in context : proficiency level English / Hugh Gethin
Modern guide to synonyms / S.I. Hayakawa
Dictionary of contemporary American usage / Bergen Evans
Pronounciation / Daniel Jones
Doubleday dictionary for home, school and office / Sidney I. Landau
Basic way to English / C.K. Ogden
Kamus idiom lengkap / Herpinus Simanjuntak
theConcise Oxford dictionary of current English / H.W.Fowler, F.G.Fowler
The Art of writing / Geoffrey Ashe
TheArt of speaking / William R. Gondin, Edward W. Mammen