27 CFR §44.87

If the application for permit or other qualifying documents are signed by an attorney in fact for an individual, partnership, association, company, or corporation, or by one of the partners for a partnership, or by an officer of an association or company, or, in the case of a corporation, by an officer or other person not authorized to sign by the corporate documents described in § 44.83, power of attorney conferring authority upon the person signing the documents shall be manifested on Form 5000.8 in accordance with its instructions.