Top 15 Digital Textbooks this 2015! December 15, 2015 With another school term coming close to an end, we decided to take a look at the most popular selling digital textbook titles sold this year at RedShelf! Check out these 15 eTextbook titles that were the top sellers and most popular in 2015!15. The Intrepid Pilgrim 14. La lengua que heredamos 13. Trigonometry 12. Human Geography in Action 11. Human Resource Management, 2nd Edition 10. You May Ask Yourself 9. Campbell Biology 8. Rules for Writers 7. "They Say/I Say": The Moves That Matter in Academic Writing 6. A Writer's Reference 5. Business and Society, 5th Edition 4. Basics of Chemistry: A Preparatory Course 3. Social Psychology 2. Functions Modeling Change 1. Information Systems for Business We are excited to see what eTextbooks will be popular for students and readers in 2016!