Hello, here I am providing you the list of the best books to refer for the GRE exam as under:

Books to refer:
Manhattan Guides – 4th edition
ETS official Guides, 2012 and 2014 editions
GRE Big Book
5 lb. Book of GRE Practice Problems – Manhattan Prep
Barron’s 1100 Book for Vocabulary, Magoosh Flashcards, Manhattan 500 Advanced Words
2 Power prep Mocks, 6 Manhattan Mocks, 6 Barron’s Mocks
Nova’s GRE Prep Course Book and the Nova GRE Math Bible
1,014 GRE Practice Questions, 3rd Edition by Princeton Review
Princeton Review – Cracking the GRE with 4 Practice Tests, 2014 Edition
Barron’s GRE, 20th Edition
GRE for Dummies with Online Practice Tests
Cliffs Notes Math Review for Standardized Tests
Gruber’s Complete GRE Guide 2015
Cracking the GRE Premium Edition 2016 with 6 Practice Tests
Kaplan GRE Complete 2016 (Books, DVD, Online)

Tips for the exam:
Start early and study often
Learn Vocabulary in Context
Take Your Online Practice Tests Seriously
Root out every mistake and make sure that these “holes in the foundation” get filled
Review your notes, especially problems and concepts that you have struggled with. It’s important to have everything you’ve learned fresh in your mind on test day.
Any practice you do at this point should be timed.
Work on your weaknesses as much as you can.