law: Interest on Delayed Payments to Small Scale and Ancillary Industrial Undertakings Act, 1993 
  3. Liability of buyer to make payment 
  Where any supplier supplies any goods or renders any services to
  
  any buyer, the buyer shall make payment therefor on
  
  or before the date agreed upon between him and the supplier in writing or,
  
  where there is no agreement in this behalf, before the appointed day.