The attendance of witnesses who are authorized to be summoned, and the production of documentary evidence authorized to be ordered, under subsection (a) may be required from any place in the United States at any designated place of hearing. In the case of disobedience to a subpoena authorized under subsection (a), the committee may request the Attorney General of the United States to invoke the aid of any district or territorial court of the United States in requiring the attendance and testimony of witnesses and the production of documentary evidence. Such court, within the jurisdiction of which such inquiry is carried on, may, in case of contumacy or refusal to obey a subpoena issued to any individual, partnership, corporation, association, organization, or other entity, issue an order requiring such individual or entity to appear before the committee, or to produce documentary evidence if so ordered or to give evidence concerning the matter in question. Any failure to obey such order of the court may be punished by such court as a contempt thereof.
Any court referred to in subsection (b) shall have jurisdiction to issue writs of mandamus commanding compliance with the provisions of this section or any order of the committee made in pursuance thereof.
The committee may order testimony to be taken by deposition at any stage of the committee review. Such deposition may be taken before any person designated by the committee and having power to administer oaths. Such testimony shall be reduced to writing by the person taking the deposition, or under the direction of such person, and shall then be subscribed by the deponent. Any individual, partnership, corporation, association, organization, or other entity may be compelled to appear and be deposed and to produce documentary evidence in the same manner as witnesses may be compelled to appear and testify and produce documentary evidence before the committee, as provided in this section.