Section 457(3) in The Gujarat Provincial Municipal Corporations Act, 1949
(3)Municipal Officers and Servants-(a)The qualifications necessary for and the method of appointment to posts the power of appointment to which vests in the Corporation;(b)the mode of appointment to other posts;(c)the powers and duties of the Municipal Chief Auditor and his staff;(d)the determination of the services under the municipality to be treated as essential services for the purposes of Chapter V.