Section 9(2) in The Rajasthan Municipal Service Rules, 1963
(2)a candidate belonging to category (c) or (d) above must be a person in whose favour a certificate of eligibility has been given by the Government of India and if he belongs to category (d), the certificate of eligibility will be valid only for a period one year from the date of his appointment beyond which he can be retained in service only if he has become a citizen of India;
