3452.     ---------------.  [TROPSCH, H.]  [Conversion of Coal Into Oils.]  Ges. Abhandl. Kenntnis Kohle, vol. 8, 1929, pp. 348-355; Chem. Zentralb., 1929, II, p. 3266; Chem. Abs., vol. 24, 1930, p. 5461.

        Survey of the known methods of producing liquid fuels from mineral coals either directly or indirectly by primary gasification.