hello piyush...,

the question you asked is quite interesting, the more you refer the books and learn the more the chance of you to get admission and get good marks and ranks in exxaminations. it depends on oneselves, the number of reference books to be studied or referred because some people maybe satisfied themselves by learning from some of the reference books whereas some others may not be satisfied and they may not get the relevent topic clarified or wouldnt get the solution to the question they are seeking for. this applies to you too, and it depends on your satisfaction and knowledge you obtained from the book and topic.

hope this information was useful to you ..

all the best for your future