1. —Tottie, G (2002) An Introduction to American English. Blackwells
2. —Publication Manual of the American Psychological Association (2001, 5th ed.) American Psychological Association, Washington DC
3. —Kortmann, B (2003) Handbook of Varieties of English. Mouton De Gruyter
4. —Webster's Standard American Style Manual (1985) Merriam-Webster
5. —Strunk, W and White, E B (1972, 2nd ed.) The Elements of Style. Macmillan, New York