Short Note : The short question involved in the petition is whether the impugned notices issued under S. 17 (3) and S. 18 (4) (a) of the Act are liable to be struck down, having been issued beyond the period prescribed by section 18 (8) (I) of the Act. 2. The contention that the notices are invalid is based on the assumption that at the time when the notices were issued, i. e., 18-2-1969, section 18 (8) was in force. 3. Held: Originally, the Act as it stood did not provide for any period during which an assesment had to be made. The period of five years, therefore, was prescribed for the first time by S. 18 (8) (1) which was inserted by the M. P. General Sales Tax (Amendment and Validation) Act, 1970, which came into force on 13-2-1970. By the M. P. General Sales Tax (Amendment and Validation) Act, 1970 which by section 4, inserted section 18 (8) in the Principal Act, the Additional Sales Tax Officer had the power to complete the assesment within a period of three calendar years under proviso (b) to section 18 (8) from the date of commencement of the Validating Act, i. e. within three years from 13-2-1970. No doubt the period specified therein has expired because of the ad-interim writ granted in these proceedings but having regard to the provisions contained in S. 20 (2) of the Act, the period during which the ad-interim stay continued has to be excluded in computing the period provided for by proviso (b) to section 18 (8) of the M. P. General Sales Tax Act. Thus the impugned notices issued by the Additional Sales Tax Officer under section 17 (3) and 18 (4) (a) of the M. P. General Sales Tax Act, 1958 are not invalid. Petition dismissed.