1. a ELF PETROLEUM CORPORATION , NEW YORK , NEW YORK , 10019 , USA
2. b PRODUCTION SCALE GAS CHROMATOGRAPHY , ELF FRANCE, BP 22, 69360 , ST SYMPHORIEN D'OZON , FRANCE
3. c LABORATORY OF ANALYTICAL PHYSICAL CHEMISTRY , ECOLE POLYTECHNIQUE , 91128 , PALAISEAU-CEDEX , FRANCE