Application and Procedure of Refund :
The application for refund shall be accompanied by –
(a) Such documentary evidence as may be prescribed to establish that a refund is due to the applicant, and
(b) Evidence that incidence of duty has not been passed on by him to any other person. However, where the amount claimed as refund is less than two lakh rupees, self-declaration based on documents available with him is sufficient. – section 54(4) of CGST Act.