(e)the provisions of the entries against serial number 12 thereof shall be subject to the following conditions:––(i)the applicable schemes of the said companies or authorities or societies or Universities or the institutes referred to in clauses (h)(vii) and (x), governing the payment of such amount are made as per such guidelines (including, inter alia, criteria of economic viability) as may be issued in this behalf;(ii)where deduction has been allowed to an employee in respect of the said item for any tax year, no deduction thereunder shall be allowed to him in relation to any other tax year; and(iii)where any relief under section 157 has been allowed to an assessee for any tax year in respect of any amount referred to in the said item, such amount shall not be allowed as a deduction from the compensation received or receivable in any tax year;