Refund of Voluntary Disclosure Payments: invalid declarations permit repayment when void ab initio, subject to claim procedure. Refunds of tax paid or amounts invested in notified securities may be made where a declaration under the Voluntary Disclosure scheme is void under the Act's exclusionary provision, because the statutory bar applicable to valid declarations does not apply to declarations that are ab initio void; such refunds follow the same claim procedure as for late declarations. Erroneous investments made in bonds pursuant to post-search declarations may likewise be refunded after Commissioner certification and referral to the Reserve Bank, and Commissioners must obtain duplicate applications, verify bona fides, and maintain registers and prompt deposit procedures.