#voucher__coupon  a negotiable certificate that can be detached and redeemed as needed
  supertype:  commercial_document__commercial_instrument  a document of or relating to commerce
  subtype:  luncheon_voucher__meal_ticket  coupon redeemable at a restaurant and entitling the holder to a meal
  subtype:  twofer  a coupon that allows the holder to purchase two items (as two tickets to a play) for the price of one

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