1. Examen, dans le cadre du bassin houiller lorrain, des possibilités stratigraphiques de la géochimie;Alpern;Ann. Soc. Géoligique du Nord,1968
2. Silicate minerals in organic-rich deposits in Southern Louisiana;Bailey,1983
3. Forms of binding of germanium in solid fuels;Bekyarova;Fuel,1971
4. Exchange capacity of peat with respect to alkali and alkaline-earth metals;Bel'Kevich,1968
5. Comparison of inorganics in three low-rank coals;Benson;Div. Fuel Chem. Amer. Chem. Soc.,1983