title: Changes to the National Physical Laboratory primary standards for x-ray exposure and air kerma.
authors.affiliation: Division of Radiation Science and Acoustics, National Physical Laboratory, Teddington, Middlesex, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Moretti
mesh_terms: D011874:Radiometry / Q000592:standards*; D006113:United Kingdom