30 Del. C. § 513

(a) The Director may prescribe rules or regulations with respect to the keeping of records, and may prescribe the content and form of returns and statements and the filing of copies of federal returns and determinations. The Director may require any person, by regulation or notice served on such person, to make such returns, render such statements or keep such records as the Director may deem sufficient to show whether or not such person is liable under this title or Title 4 for the payment of any tax or for the collection of any tax. The Director may permit or require the filing of returns by electronic means or by magnetic media and, in either case, may specify the form and content of such filing.

(b) Notwithstanding any other provision of law, any return, declaration, statement or other document submitted by means of a digital or electronic form stating that the submission is subject to the penalties of perjury shall be treated for all purposes (both civil and criminal, including penalties for perjury) in the same manner as though signed or subscribed.