42 C.F.R. § 137.173 Does a Self-Governance Tribe have a right of appeal from a disallowance?
Title 42 - Public Health
Yes, the notice must set forth the right of appeal and hearing to the Interior Board of Contract Appeals, pursuant to section 110 of the Act [25 U.S.C. 450m–1].
Title 42: Public Health
PART 137—TRIBAL SELF-GOVERNANCE
Subpart I—Operational Provisions
Audits and Cost Principles
§ 137.173 Does a Self-Governance Tribe have a right of appeal from a disallowance?

