Powers of auditor

The auditor may,— (a) by summons in writing, require production of any document, the perusal or examination of which he believes necessary for the elucidation of the accounts; (b) by summons in writing, require any person who has the custody or control of any such document or who is accountable therefore to appear in person before him; and (c) require any person so appearing to make and sign a declaration with respect to such document or to answer any question or to prepare and furnish any statement relating thereto.