Section 42. Whenever a city, town or district causes an audit of its accounts or the accounts of separate departments to be made by a firm or person of its own selection, the city, town or district clerk shall immediately, upon the employment of such firm or person, file the name and address with the director, and such firm or person shall, within 10 days after making the report of the audit and recommendations to the city, town or district, file a certified copy thereof with the director.