Section 19(3)(b) in Insolvency and Bankruptcy Board of India (Liquidation Process) Regulations, 2016
(b)other relevant documents which adequately establish the dues, including any or all of the following -(i)a proof of employment such as contract of employment for the period for which such workman or employee is claiming dues;(ii)evidence of notice demanding payment of unpaid amount and any documentary or other proof that payment has not been made; and(iii)an order of a court or tribunal that has adjudicated upon the non-payment of dues, if any.