25 U.S. Code § 4192 - Security and repayment
The full faith and credit of the United States is pledged to the payment of all guarantees made under this subchapter. Any such guarantee made by the Secretary shall be conclusive evidence of the eligibility of the obligations for such guarantee with respect to principal and interest, and the validity of any such guarantee so made shall be incontestable in the hands of a holder of the guaranteed obligations.
This chapter, referred to in subsecs. (a) and (b), was in the original “this Act”, meaning Pub. L. 104–330, Oct. 26, 1996, 110 Stat. 4016, known as the Native American Housing Assistance and Self-Determination Act of 1996. For complete classification of this Act to the Code, see Short Title note set out under section 4101 of this title and Tables.