The Secretary of the Interior, or his duly authorized representative, is authorized in his discretion, and upon application of the Indian owners, to issue patents in fee, to remove restrictions against alienation, and to approve conveyances, with respect to lands or interests in lands held by individual Indians under the provisions of the Act of () [ et seq.], or the Act of ().48 Stat. 98425 U.S.C. 510149 Stat. 1967June 18, 19341934-06-18June 26, 19361936-06-26