Public Utility Holding Companies: Hearings Before the Committee on Interstate and Foreign Commerce, House of Representatives, Seventy-fourth Congress, First Session, on H.R. 5423, to Provide for Control in the Public Interest of Public Utility Holding Companies Using the Mails and the Facilities of Interstate Commerce, to Regulate the Transmission and Sale of Electric Energy and Natural Gas in Interstate and Foreign Commerce, and for Other Purposes, Parts 1-3