API MPMS 11.4.1 pdf download.Manual of Petroleum Measurement Standards Chapter 11—Physical Properties Data 4 Definitions 4.1 density, absolute: The density of a solid or liquid substance at a speciÞed temperature is the mass of the sub- stance occupying a unit of volume at the speciÞed tempera- ture. Density so deÞned is sometimes referred to as Òtrue densityÓ or as Òdensity...