Contents of proof require affidavits to state debt particulars, vouchers, and creditor security status in prescribed form. An affidavit proving a debt must include or refer to a statement of account showing particulars of the debt, specify any vouchers by which it can be substantiated, state whether the creditor is a secured creditor or a preferential creditor and set out particulars of such security or preferential claims, and must be in Form WIN 44.