If a receipt has been lost or could not be secured, a signed statement by a trustworthy person or persons standing in witness to the expenditure, can be attached as a substitute receipt to the Purchase Order or Voucher. An example is travel approved after-the-fact, when the traveler was not aware they might be compensated for gas or milage and failed to retain receipts. Such signed statements should explain the nature of the expenditure, state the means by which witness to the expenditure occurred, and state how the value of the expenditure was accertained. Such statement should be signed and dated and delivered to the Treasurer.