Hi, you have asked really a good question because most of the students hesitating to ask about it practically and surfing the internet for the answer. It is hard to decide to choose the best answer among the lots of answers on the internet. But from my personal experience I would like to give you one best suggestion being myself as a student. I never read any reference books because I believe that if you read NCERT textbook to your most core level with the last 7 years Board question Paper and few latest sample paper. You definitely get 90+ percentage in class 10. And also I got 92.77 percentage.