BS 2000-346:1996 Methods of test for petroleum and its products - Determination of polycyclic aromatics in unused lubricating base oils and asphaltene free petroleum fractions - Dimethyl sulphoxide extraction refractive index method
1996BS 2000-346:1996 Methods of test for petroleum and its products - Determination of polycyclic aromatics in unused lubricating base oils and asphaltene free petroleum fractions - Dimethyl sulphoxide extraction refractive index method