Section 21(2) in The Employees' State Insurance (Central) Rules, 1950
(2)The receipt book in Form I shall be numbered serially by machine and the unused forms shall be kept in the custody of the [Financial Commissioner] [ Substituted by G.S.R. 76, dated 22.1.1991 (w.e.f. 1.2.1991).] or such other officer of the Corporation as may be authorised by the Corporation in this behalf.
