Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. Interpretation of Law or Regulation: Butane, Propane, or Similar Automatic Gas Systems, Included in Group E of Supplement, Number S-363, Volume 55, Page 333, Mimeograph Letters and Statements of the Board. Board of Governors of the Federal Reserve System (U.S.), 1935-. https://fraser.stlouisfed.org/archival/4957/item/509658, accessed on October 16, 2026.