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16 U.S. Code § 521c - Definitions

For purposes of sections 521c to 521i of this title—
the term “person” includes any State or any political subdivision or entity thereof;
the term “interchange” means a land transfer in which the Secretary and another person exchange titles to lands or interests in lands of approximately equal value where the Secretary finds that such a value determination can be made without a formal appraisal and under such regulations as the Secretary may prescribe; and
the term “Secretary” means the Secretary of Agriculture of the United States.