In every school district of the second and third classes, the proper auditors herein provided to audit the finances of the school district shall begin their duties on the first day of July each year, and promptly within thirty days audit the accounts of the school district for which they were appointed, including the accounts of the treasurer, the school depositories, and other school funds, for the preceding fiscal year, in the manner herein provided. On the completion of the audit they shall make correct copies thereof, which shall contain an itemized statement of all receipts, expenditures, and credits, whatsoever, of school officials, and the assets and liabilities of the district. One copy shall be filed with the board of school directors of the district, one copy in the court of common pleas of the county in which the district is located, and one copy with the intermediate unit board of directors, one copy in the Department of Public Instruction,¹ by mailing the same sealed, stamped, and addressed to the Superintendent of Public Instruction, Harrisburg, Pennsylvania, by registered mail with return registry receipt requested.