The Official Guide for GMAT Review 2015 Bundle (Official Guide + Verbal Guide + Quantitative Guide)
Cracking the GMAT Premium Edition with 6 Computer-Adaptive Practice Tests, 2015 (Graduate School Test Preparation)
Kaplan GMAT in a Box
Manhattan GMAT Complete Strategy Guide Set, 5th Edition [Pack of 10] (Manhattan Gmat Strategy Guides: Instructional Guide)
Complete GMAT Strategy Guide Set, 6th Edition