It is not necessary to clear the UPSC Exam under the guidance of any famous coaching institute. Self study is enough to crack IAS exam. Books (IAS Study Material) are the best friend of a student. It's not necessary to read heavy-weight book but you need to read a single book in which all topics are covered. A lot of books are available in market but you need to buy some selective books for preparation. Study in designed time table is best strategy for UPSC exam preparation.
Click on the following link to free download NCRET Books: http://www.atoztyari.com/ias/free-ias-books.php
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