In carrying out its duties under this section, the Commission, or any duly authorized committee thereof, is authorized to hold such hearings, sit and act at such times and places, and take such testimony, with respect to matters with respect to which it has a responsibility under this section, as the Commission or such committee may deem advisable. The Chairman of the Commission or any member authorized by him may administer oaths or affirmations to witnesses appearing before the Commission or before any committee thereof.