Hello Varun,
There are so many referral books in the internet which were free and also you can find the referral book which is good for you in this online source. Some books are free to read in the online source and some are paid and get the book.
Hope this help you.
College Comparison based on Courses, Placement, Rank, Fee
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile