1. "Word Power Made Easy" by Norman Lewis
2. "The Vocabulary Builder Workbook" by Chris Lele and Magoosh
3. "30 Days to a More Powerful Vocabulary" by Wilfred Funk and Norman Lewis
4. "Merriam-Webster's Vocabulary Builder"
5. "The Elements of Style" by William Strunk Jr. and E.B. White
6. Building a Better Vocabulary" by Kevin Flanigan
7. Vocabulary Cartoons: SAT Word Power" by Sam Burchers and Max Burchers.