If the tribal member's principal residence is on "Indian country" as defined in 18 U.S.C. Section 1151, the income earned on Indian country may be deducted. Legally acknowledged Indian country must be within the jurisdiction of the tribe of which he or she is a member. All claimants must provide sufficient information to support that these requirements have been satisfied. Provide the following information for tax year 2013: a. A copy of your tribal membership card or certification by your tribe as to your tribal membership during the tax year; and b. A copy of the trust deed, or other legal document, which describes the real estate upon which you maintained your principal place of residence and which was an Indian allotment, restricted, or held in trust by the United States during the tax year. If your name does not appear on the deed, or other document, provide proof of residence on such property; and c. A copy of the trust deed, or other legal document, which describes the real estate upon which you were employed or performed work or received income and which was held by the United States of America in trust for a tribal member or an Indian tribe or which was allotted or restricted Indian land during the tax year. Also a copy of employment or payroll records which show you are employed on that Indian country or an explanation of your work on Indian country; and d. Any other evidence which you believe supports your claim that you meet all of the criteria for exemption from income tax. If you are mailing your return, be sure to include this information with your return. If you are e-filing your return, retain the information in your records for three years in case the Oklahoma Tax Commission requests it.