1. Introduction to Formal Languages, Automata Theory and Computation, 
        by Kamala Krithivasan and Rama R, Pearson, 2009, 
        ISBN 978-81-317-2356-2

1a. Introduction to the Theory of Computation, by Michael Sipser, (2nd ed.)
        Pub. Brooks/Cole, Thomson Learning, ISBN 981-240-226-8

1b. Introduction to Automata Theory, Languages, and Computation, by
        John E. Hopcroft, Rajeev Motwani, and Jeffrey D. Ullman,
        Pub. Pearson Education Asia, ISBN 81-7808-347-7

1c. Elements of the Theory of Computation, by Harry R. Lewis and
        Christos H. Papadimitriou, 
        Pub. Prentice-Hall of India, ISBN 81-206-1016-0

1d. Automata and Computability, by Dexter C. Kozen, Pub. Springer,
        ISBN 3-540-78105-6, Rs 325/-

1e. Introduction to Languages and the Theory of Computation (3rd ed.),
	by John Martin, TMH, ISBN 0-07-049939-X

2. Theory of Computer Science, by K. L. P. Mishra and N. Chandrasekaran,
        Pub. Prentice-Hall of India, ISBN 0-87692-632-4

  There are large number of good books on this subject.