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16 U.S. Code § 404e - Donations of money; acquisition of title to lands

In the establishment of the said Mammoth Cave National Park the Secretary of the Interior is authorized to accept donations of money for the acquisition of lands and rights therein and to acquire the same by purchase, condemnation, or otherwise.

(May 14, 1934, ch. 282, § 2, 48 Stat. 775.)