no doubt that books are the best source than notes.as u didn't mentioned your subjects so how can someone guide you about the right books.when someone asked on forum about books everybody guide according to his own experience,study and books, don't be confused.just choose that books which are suggested by majority or csp,s.and try to make your own notes its best.and three months are enough its not a short period so don,t worry start it with devotion.best of luck

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